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Course Outline
   Introduction to Network Storage             D-Link NAS (Network Attached
   RAID Technologies                            Storage)
   Storage Essentials                            •   D-Link Products for Network
     •   Basic Terminologies and Concepts             Attached Storage
     •   Hard Drive Interface Technologies        •   Market Analysis for D-Link NAS
                                                      Products
   SAN Technologies
     •   Fiber Channel Technology               NAS Product Features Overview
     •   iSCSI Technology                         •   Managing the Device
   D-Link SAN (Storage Area Network)             •   User and Group Management
     •   D-Link Products for Storage Area         •   Appliance Servers
         Network                                  •   Network Features
     •   Market Analysis for D-Link SAM           •   USB Port Applications
         Products
                                                Applications and Solutions for
     •   D-Link SAN Implementation
                                                 Network Storage
   SAN Product Features Overview
                                                  •   NAS Applications
     •   Volume Management
                                                  •   SAN Applications
     •   Device Management
     •   iSCSI Features
     •   Volume and RAID Support
                                                                                       2
DCS – Storage

Introduction to
Network Storage

                  3
                                          Introduction to Network Storage




Introduction to Network Storage




After this section, you should gain more knowledge of the following:
1. Types of current storage solutions for computerized devices
2. Characteristics of DAS and the challenges of using it
3. Characteristics of NAS and the benefits/advantages that it offers
4. Characteristics of SAN and the benefits/advantages that it offers
5. Differences among each storage solution

                                                                            4
                                                       Introduction to Network Storage
                                                                      Storage Evolutions




     Evolutions of Storage Technology
                                       1963                             1982

   1940             1951   1956     1962        1970          1978   1981      1984
        1940s – Data was mostly stored on punched card and punched paper tape.
        1951 – First computer to use magnetic tape for storage.
        1956 – IBM introduced the first commercial hard disk drive known as RAMAC
         (Random Access Method of Accounting and Control).
        1962 – The laser diode was invented by IBM which became the fundamental
         technology for read-write optical storage devices.
        1963 – IBM introduced the first storage unit with removable disks. This became
         an end for punched-cards era.
        1970 – Portable storage was born with the invention of the floppy disk.
        1978 – The first patent for RAID technology was filed.
        1981 – The Intelligent interface for disk drive ―SASI‖ was developed by Shugart
         Associates and NCR Corporation. This interface is the predecessor to SCSI
         interface.
        1982 – SCSI interface was born and developed based on its predecessor, SASI.
        1984 – Compaq and Western Digital Co. produced ST506 controller that was able
         to be mounted on the hard disk drive and connected to the PC using a 40-pin
         cable.
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                                                         Introduction to Network Storage
                                                                      Storage Evolutions




     Evolutions of Storage Technology (cont’d)
                           1986                                            2001

                    1985                 1994     1996      1998    2000          2003
        1985 – First IDE drive was built by integrating ST506 controller in the hard disk
         drive.
        1986 – SCI specification was defined in a ANSI standard X3.131-1986.
        1994 – SCSI-2 became an ANSI standard X3.131-1994 and the IDE standard was
         approved by the ANSI under the name ANSI X3.221-1994.
        1996 – The ATA-2 interface that complied with the ANSI X3.279-1996 standard
         was the AT Attachment Interface with Extensions, and the ATA-2 interface that
         complied with the ANSI X3.279-1996 standard was the AT Attachment Interface
         with Extensions.
        1998 – The ATA/ATAPI-4 interface that complied with the ANSO NCITS 317-1998
         was the AT Attachment Interface with Packet Interface Extension.
        2000 – The ATA/ATAPI-5 interface that complied with the ANSI NCITS 340-2000
         was the AT Attachment Interface with Packet Interface-5.
        2000 – The Serial ATA 1.0 Working Group was established to specify Serial ATA
         for desktop applications.
        2001 – Serial ATA 1.0 was released in August of 2001 (with subsequent revisions
         1.0a and 1.1) which provided significant improvement over parallel ATA.
        2003 – Hitachi bought IBM Data Storage Division.

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                                                Introduction to Network Storage
                                                               Storage Solutions




Types of Storage Solution
   Internal Storage                      External Storage
     •   Memory (DDR)                       •   Direct Attached Storage (DAS)
     •   IDE ATA Hard Disk / Optical        •   Network Storage
         Compact Disk                            – Network Attached Storage (NAS)
     •   SCSI Hard Disk                          – Storage Area Network (SAN)
     •   SATA Hard Disk                     •   USB Storage Enclosure
                                            •   Firewire 1394 Storage Enclosure
                                            •   Slim Disk Memory




                                                                                    7
                                                  Introduction to Network Storage
                                                                Storage Solutions




Direct Attached Storage (DAS)
   A storage system directly attached                    Oracle
    to a client (commonly to a                           Database
    computer or server), without a                        Server Host Bus Adapter
    storage network in between.
   Common example of DAS would be                                         DAS #1
                                         Local
    a storage enclosure externally       Area               File Server
    attached to a server, where clients Network
    in the network must access the
                                                                           DAS #2
    server in order to connect to the
    storage device.
                                                           Active Directory Server

                                       Client
                                                                           DAS #3

                                                           Network Application Server


                                                                           DAS #4




                                                                                        8
                                          Introduction to Network Storage
                                                       Storage Solutions




Challenges of DAS
   Difficulty managing servers and storage with slow backup causing
    heavy LAN congestion
   Limited number of drives supported
   Limitation on storage size
   Inability to share storage across multiple servers
   Time-consuming and complex backup and management
   Need for storage down time (off-line) when installing additional
    drives




                                                                            9
                                              Introduction to Network Storage
                                                            Storage Solutions




Solution for DAS
   Simplify storage management by separating the data from application
    server.

                     DAS  Network Storage




                                                                                 10
                                              Introduction to Network Storage
                                                           Storage Solutions




Why Do We Need Network Storage?
   Volume of data keeps growing exponentially
   Redundancy and backup necessity
   Data availability and accessibility
   Storage consolidation for centralized management*
   Increase reliability and better performance (speed)
   Storage virtualization*
   Overall cost reduction
   Data Protection




    * Unique characteristics possessed by SAN only.


                                                                                11
                                                Introduction to Network Storage
                                                               Storage Solutions




Network Attached Storage (NAS) Overview
   NAS is a file-level computer data storage device connected to a computer
    network providing data access to heterogeneous network clients.
   A NAS unit is essentially a self-contained computer connected to a network,
    with the sole purpose of supplying file-based data storage services to other
    devices on the network.
   NAS are usually accessed by workstations and servers through a network
    protocol such as TCP/IP and applications such as Network File System
    (NFS) or Common Internet File System (CIFS) / Server Message
    Block (SMB) for file access.

                    File Server   Public Local Area Network




             Application Server

                                                           NAS

                        Client

                                                                                    12
                                                           Introduction to Network Storage
                                                                        Storage Solutions




Storage Area Network (SAN) Overview
   A high performance storage network that transfers block-level data between
    servers and storage devices, separate from the local area network (LAN) traffic.
   In a SAN environment, storage devices, such as DAS, RAID arrays, or tape
    libraries are connected to servers using fiber channel or iSCSI.
   Characteristics of SAN:
     •   Virtualization
     •   Storage Consolidation
     •   Scalable
     •   Block data transfer uses encapsulated SCSI

                                           File Server        High performance
                                                           private storage network
                      Public
                                                                       SAN
               Local Area Network




                                      Application Server
           Client


                                                                                             13
                                                       Introduction to Network Storage
                                                                        Storage Solutions




Differences of NAS and SAN
    Network Attached Storage (NAS)                    Storage Area Network (SAN)
• Clients sees the NAS box as an                • Client sees the SAN as a part of a server
  independent device (as a file server), thus     (the SAN is connected behind the server in
  the architecture is client-server based         its own network), thus client should
  where client requests are sent directly         send the request to server connected to
  to the NAS.                                     the SAN.
• Clients connect to a NAS and share files      • Clients connected to the SAN through the
  through the use of NFS, CIFS/SMB, or            use of iSCSI or Fiber Channel,
  HTTP protocol.                                  depending on which is supported by the
                                                  SAN.
• File-based data transfer (data is             • Block-level data transfer along long
  identified by file name and other               distances (data is addressed by disk block
  parameters, such as the file meta-data          number and without file system
  (file‘s owner, permissions, etc)                formatting).
• Backups and mirrors are done on files, not    • Backups and mirrors require a block by
  blocks, which provides savings in               block copy, even if blocks are empty. A
  bandwidth and time.                             mirror machine must be equal to or
                                                  greater in capacity than the source
                                                  volume.
                                                                                               14
                                                            Introduction to Network Storage
                                                                                 Storage Solutions




Comparison for each of the Storage Solutions
      DAS Enclosure                     NAS Enclosure                         SAN Enclosure
Directly connected to a client   Connected to servers and         Connected to servers over
                                 workstations via a pubic         the private storage
                                 network                          network
Slower data access               Fast data access (depends        Fastest data access (depends
compared to network              on the LAN speed)                on which protocol is used)
storage
Direct data transfer             File level data transfer         Block level data transfer

Data transfer using SCSI         Data transfer using NFS /        Fiber Channel or iSCSI is
protocol                         CIFS / SMB protocol              used for data transfer
                                                                  protocol

                                                                                                 High performance
                                                                                   File           private storage
                                                                                  Server             network
                                                                   Public LAN


                                                                                                             SAN
                                                                                                           Appliance



                                                                     Client        Application
                                                                                     Server




                                                                                                                       15
                                          Introduction to Network Storage
                                                               Summary




Summary: Introduction to Network Storage
   Clients can choose from three types of storage systems to keep
    their data on: Direct Attached Storage (DAS), Network Attached
    Storage (NAS), and Storage Area Network (SAN).
   Direct Attached Storage (DAS) is the most commonly used data
    storage solution for end user level client devices (computers,
    servers). It attaches the storage enclosure directly to the client
    device.
   Network Attached Storage (NAS) is mainly targeted for home and
    SMB users, and offers the benefits of network storage with ease of
    sharing files and centralized data storage over the IP network.
   Storage Area Network (SAN) is mainly targeted for Server Farms or
    Special Applications, e.g. IP Surveillance, and offers high
    performance network storage solutions for data transfers over
    enterprise network, with benefits include virtualization, storage
    consolidation, etc.
   D-Link supports data transfer over the iSCSI protocol for SAN
    devices.
                                                                            16
                                                    Introduction to Network Storage
                                                                Questions and Answers



Questions and Answers:
Introduction to Network Storage
1. What is the characteristic of Direct Attached Storage?
    A. Storage is connected to the server without being separated with TCP/IP
       network
    B. Storage consolidation capability
    C. Data transfer using Network File System (NFS) protocol
    D. Link multiple storage repositories to multiple clients and servers

2. What is the characteristic of D-Link Network Attached Storage?
    A.   Provide slow data access
    B.   Block data transfer along long distance is possible
    C.   Data transfer using CIFS/SMB protocol
    D.   Support server virtualization

3. What are the characteristics of D-Link Storage Area Network? (Choose
   Two)
    A.   File-level data transfer along long distance
    B.   Storage is connected directly to the server using iSCSI protocol
    C.   Block data transfer
    D.   Support storage virtualization and consolidation

                                                                                         17
DCS – Storage

RAID Technologies


                    18
                                                     RAID Technologies




RAID Technologies




After this section, you should gain more knowledge of the following:
1. RAID mechanisms overview
2. RAID types supported by D-Link network storage appliances
3. Characteristics of each RAID type supported by D-Link as well as
   the advantages and disadvantages for each (RAID 0, RAID 1, RAID
   5, RAID 10, and JBOD)

                                                                         19
                                                                                RAID Technologies
                                                                              Introduction to RAID




RAID Technology Overview
     Redundant Arrays of Independent Disks (RAID) is a data storage mechanism
      for dividing and/or replicating data over multiple hard drives, thus which
      may provide better performance, reliability, and/or larger data volume sizes.
      Depending on the type of RAID applied, different benefits can be achieved.
     D-Link network storage supports several RAID technologies as described
      below:
    RAID Level    Type                         Definition                       Redundant   Striped
      RAID 0     Striped    Distributes each block of data among several           No         Yes
                            drives to improve the speed of access
      RAID 1     Mirrored   Two copies of all data are written to                  Yes        No
                            independent disks
     RAID 10     Mirrored   Stripes the data among several drives and then         Yes        Yes
                 Striped    mirrors the data to another set of disks
      RAID 5      Parity    Distributes one copy of the data among several         Yes        Yes
                            drives and adds parity blocks spread
                            throughout the volume to protect against the
                            loss of any single drive
       N/A        JBOD      All the disks are grouped together to form one         No         No
                            large volume. The data is written to the disks
                            in sequential order
                                                                                                      20
                                                                                 RAID Technologies
                                                                                                  RAID 0




RAID 0 Technology Overview
   Characteristics of RAID 0
     •   RAID 0 works by striping the data (Data-striping) across the hard drives
     •   At least two hard drives must be provided
     •   Improved performance (high speed data transfer)
     •   No fault-tolerance
     •   No error-checking
   Advantages and disadvantages
                  Advantages                                          Disadvantages
• Speed enhancement and improve I/O                   • No data redundancy or fault-tolerance
  performance                                         • Failure occurring in any disk of an array
• Maximum utilization of storage capacity*              will result in all data in that array being
• Very simple design and easy to implement              lost
* Each physical disk must be of the same capacity to achieve 100% storage capacity utilization




                                                                                                            21
                                                                RAID Technologies
                                                                              RAID 0




     Illustration of RAID 0
                                 Data



          1        2         3          4   5          6

                                                              Primary Disk

          Disk-0       Disk-1
                                            Network Storage
                                                            ✕     Disk 0


              1          2                                 ✕      Disk 1
              3          4

              5          6

                                                  If RAID 0 is in use and one of
                                                  the disks in the array crashes,
                                                the rest of disks in the array will
                                                 also not work. This will result is
                                                          total data loss.
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                                                             RAID Technologies
                                                                        RAID 1




RAID 1 Technology Overview
   Characteristics of RAID 1
   RAID 1 works by mirroring the data
   At least two hard drives must be provided
   Fault-tolerance
   Advantages and disadvantages

             Advantages                            Disadvantages
• 100% data redundancy                  • Highest disk overhead of all RAID
                                          types
                                        • Inefficient because only 50% of the
                                          physical drive storage‘s capacity is
                                          used




                                                                                  23
                                                               RAID Technologies
                                                                         RAID 1




     Illustration of RAID 1

                                   If RAID 1 is in use and the primary disk
             Disk-0       Disk-1
                                        crashes, the mirrored disk will
                   1        1      automatically replace the primary disk.
                   2
                   3
                            2
                            3
                                             Network Storage    ✕     Primary Disk

                   4        4
                                                                      Mirrored Disk

             100% Redundancy!!!




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                                                                RAID Technologies
                                                                           RAID 5




RAID 5 Technology Overview
   Characteristics of RAID 5 technology:
    • Striped set with distributed parity
    • Minimum three disks must be provided to implement RAID 5
    • Offers data protection and increases throughput

   Advantages and Disadvantages
              Advantages                               Disadvantages
• 100% data protection                      • Extra time needed to calculate the
• Offer more physical drive storage           parity
  capacity than RAID 1                      • Disk failure has a medium impact on
• Highest read data transaction rate          throughput
• Distributing the parity over all of the   • Difficult to rebuild volume in the
  disks rather than putting all the           event of a disk failure (as compared
  parity on one disk                          to RAID level 1)



                                                                                     25
                                                                                    RAID Technologies
                                                                                                      RAID 5




     Illustration of RAID 5
       Data to be written: 101110011010
              Using RAID 5, if one of the disks in the array fails,
                   data in the failed disk can be recovered

       Data is fully recovered!!!




                                                ✕
                                    Disk-2 fails, data cannot be accessed!!!
                                                                         New Disk to replace
                   Disk-0       Disk-1             Disk-2                  the failed disk



                  1               0            P=1 (1 XOR 0)                   1   XOR   0   =   1
                  1         P=0 (1 XOR 1)            1                         1   XOR   0   =   1
            P=1 (1 XOR 0)         1                  0                         1   XOR   1   =   0
                  0         P=1 (0 XOR 1)            1                         1   XOR   0   =   1
                  1               0            P=1 (1 XOR 0)                   1   XOR   0   =   1
                  1         P=1 (1 XOR 0)            0                         1   XOR   1   =   0
                                                                       Rebuilt process started!


                                Data can be rebuilt to the new disk using XOR calculations by
         P: parity               recalculating the two bits retrieved from the existing drives
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                                                               RAID Technologies
                                                                       RAID 10




RAID 10 Technology Overview
   Characteristics of RAID 10 technology:
   RAID 10 provides mirroring and striping at the same time
   Minimum four disks or even number of disks is required
   Provides fault-tolerance and improves performance
   Advantages and Disadvantages
             Advantages                            Disadvantages
• Provide fault tolerance to prevent    • Expensive, many disks are required
  data loss                               to implement this RAID technology
• Provide high performance for I/O      • Only 50% of the physical drive
  operation (read and write)              storage‘s capacity is used, if
                                          implements mirroring mechanism




                                                                                   27
                                                                         RAID Technologies
                                                                                        RAID 10




Illustration of RAID 10
                                     RAID 0 - Stripe



          RAID 1 - Mirror                                       RAID 1 - Mirror



 Disk-0                     Disk-1                     Disk-2                     Disk-3



  1                          1                          2                          2


  3                          3                          4                          4

  5                          5                          6                          6




                        Very high reliability combined
                          with high performance!!!
                                                                                                   28
                                                              RAID Technologies
                                                                           JBOD




JBOD Technology Overview
   Characteristics of JBOD (Just a Bunch Of Disks):
   No Data redundancy, which means no fault-tolerance
   Bigger array capacity
   Two or more hard disks are required to create one logical drive
   Advantages and Disadvantages

             Advantages                              Disadvantages
• Provide 100% storage capacity          • No data redundancy or fault-
  utilization                              tolerance provided




                                                                                   29
                                                                    RAID Technologies
                                                                                      JBOD




Illustration of JBOD
   JBOD is usually known as concatenation where the total storage capacity
    equals to the sum of each separate disk.

                                                 Logically seen as one big storage
             Disk-0          Disk-1



              1               65

              2
                              …



                                             Total storage capacity (Σ) =
                                             capacity of Disk-0 + capacity of Disk-1
                              67
              …….




              64




                                                                                              30
                                                             RAID Technologies
                                                 Summary for Each RAID Type




Summary for Each RAID Technology
                    Data            Read          Write         Min. Number
    RAID Level
                 Redundancy     Performance    Performance       of Drives

      RAID-0          No           Superior       Superior            2

      RAID-1          Yes         Very High         High              2

      RAID-5          Yes          Superior         Good              3

     RAID-10          Yes         Very High         High              4

      JBOD            No           Superior       Superior            2

    D-Link Storage Area Network allows migration between RAID levels, but
     this is dependent on number of HDD drives available.
    The performance of each RAID level may vary depending on the hardware
     platform used.


                                                                                 31
                                                                  RAID Technologies
                                                                           Summary




Summary: RAID Technologies
   Redundant Array of Independent Disks (RAID) is a data storage mechanism that
    provides better performance and/or data reliability.
   D-Link network storage appliances support RAID 0, RAID 1, RAID 10, RAID 5,
    RAID 6 and JBOD to offer greater performance and reliability for D-Link users.
    Which types of RAID supported is dependent on the models.
   RAID 0 provides the best performance with the fastest data transfer speed by
    striping all the data to multiple disks.
   RAID 1 provides data redundancy by mirroring/duplicating the data from one disk
    to another disk.
   RAID 5 offers data protection and increases throughput by creating data parity
    and distributing it to all the provided disks.
   RAID 6 offers data protection and increases throughput by creating data parity
    and distributing it to all the provided disks. Same as RAID 5, but with 2 parity
    disks.
   RAID 10 combines both RAID 0 and RAID 1 at once, thus providing greater
    performance while also serving data redundancy to prevent single point of failure.
   Just a Bunch of Disks (JBOD) is not a type of RAID mechanism and does not
    provide data redundancy. It is used for achieving greater storage capacity among
    all the hard disks, which may come in different sized capacity.


                                                                                         32
                                                      RAID Technologies
                                                  Questions and Answers




Questions and Answers: RAID Technologies
1. Which RAID level does not support fault-tolerance for the stored
   data?
   A.   RAID 0
   B.   RAID 1
   C.   RAID 10
   D.   RAID 5
   E.   JBOD


2. Which RAID technology supports the consolidation of all disks with
   different sizes thus enlarging the capacity of available storage
   spaces?
   A.   RAID 0
   B.   RAID 5
   C.   JBOD
   D.   RAID 10

                                                                           33
DCS – Storage

Storage Essentials


                     34
                                                      Storage Essentials




Storage Essentials




After this section, you should gain more knowledge of the following:
1. Basic terminologies commonly used to explain storage technology
2. Different hard drive technologies and the characteristics of each

                                                                           35
                                                                                   Storage Essentials
                                                             Basic Terminologies and Concepts




Basic Terminologies
   Block – A sequence of bytes or bits in which data is stored and retrieved on disk and
    tape devices.
   Array – A set of physical disks grouped into one or more logical drives.
   Logical drive - A set of actual physical disks that are grouped together and behave as if
    it were a single drive as seen by the user.
   Volume – A set of blocks of storage that are organized and presented for use by the
    server.
   Logical Unit Number (LUN) – number assigned to a logical unit.
     •   It can be used to refer to an entire physical disk, or a subset of a larger physical disk or disk
         volume. The physical disk or disk volume could be an entire single disk drive, a partition (subset)
         of a single disk drive, or disk volume from a RAID controller comprising multiple disk drives
         aggregated together for larger capacity and redundancy. LUNs represent a logical abstraction
         between the physical disk device/volume and the applications. For example if you partition a disk
         drive into smaller pieces for your application or system needs (perhaps your server's operating
         system has a disk drive size limit) the sub-segments would share a common SCSI target ID
         address with each partition being a unique LUN.
     •   In an iSCSI environment, LUNs are essentially numbered disk drives. An initiator negotiates with
         a target to establish connectivity to a LUN; the result is an iSCSI session that emulates a SCSI
         hard disk. Initiators treat iSCSI LUNs the same way as if they were a raw SCSI or IDE hard
         drive. For instance, rather than mounting remote directories as will be done in NFS or CIFS
         environments, iSCSI systems format and directly manage file systems on iSCSI LUNs.
     •   In enterprise deployments, LUNs usually represent slices of large RAID disk arrays, often
         allocated one per client. iSCSI imposes no rules or restrictions on multiple computers sharing
         individual LUNs; shared access to a single underlying file system is instead left as a task for the
         operating system.



                                                                                                               36
                                                                              Storage Essentials
                                                           Basic Terminologies and Concepts




     Spare Count
        Definition of Spare
          •   Spare is an drive (drive B) which is reserved for the purpose of substituting for
              another drive (drive A) in case of a failure on drive A.
        Definition of Hot Spare
          •   Hot spare is a drive which has been flagged for use if another drive in the array
              fails
        Definition of Spare Count
          •   Spare count is the number of drives to be kept available in case a drive which
              contains a volume (with data) fails.
          When one of the active drives fails, the hot spare drive will replace the failed drive
                                    Active Drives
                                                                      Hot Spare Drive




                                                                      Spare Count = 1
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                                                                                    Storage Essentials
                                                              Hard Drive Interface Technologies




Hard Drive Interface Technologies Overview
     ATA (Advanced Technology
      Attachment)
        •   Mostly used in desktops and
            notebooks
        •   Consist of two standards:
              – PATA (Parallel ATA)
              – SATA (Serial ATA)
     SCSI
     Serial Attached SCSI (SAS)
     Fiber Channel*




     * Fiber channel is now commonly used for SAN solutions, but seldom used for end user computers.
    Though there are Fiber Channel hard drives available in the market, they are hardly found these days.
                                                                                                            38
                                                                     Storage Essentials
                                                    Hard Drive Interface Technologies




     Why SATA?
               End-User Needs
        More storage in limited space              Serial ATA Value Proposition
        Improved price/ performance
                                                Narrower Cabling
        Investment protection
                                                Supports lower power requirements
        Lower overall system cost
                                                Lower pin counts
           System Vendor Needs                  Higher performance (data rates up to
                                                 300MBps)
        Dense boxes
                                                Improved connectivity (no master/
        Similar components                      slave)
        Lower power consumption                Longer cabling (reach up to one meter)
        Increased air flow
        More motherboard space



          Serial ATA offers more features and better performance than parallel ATA



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                                                                                                          Storage Essentials
                                                                               Hard Drive Interface Technologies




     Evolution of SATA
         The Serial ATA (SATA) working group will deliver incremental specification
          releases over the next several years. These enhancements will enable the
          technology to support a variety of possible storage configurations.
                                                                                   Serial ATA II, Phase 2
                                                                                   • Second-generation speed grade for desktops
                                                                                     and network storage systems (Targeted 300
                                                                                     MB/sec)
                                                                                   • Improvements to address additional needs in
                                                                                     higher-end network storage segments
                         Serial ATA II, Phase 1                                    • Topology support for dual host active failover
                         • Improved use of SATA 1.0 technology in server and       • Efficient connectivity to larger number of
                           network storage                                           devices
                         • Backplane interconnect solution for racks of hot-swap
                           drives
                         • Complete enclosure management solution (Fan control,
                           drive lights, temperature control, new device notifications,
                           etc)
                         • Performance improvement to address industry needs
                           (firmware/ software, performance enhancements,
    Serial ATA 1.0         including native queuing)

    • Primary inside-the-
      box storage
      connection to replace
      parallel ATA

Page is Animated                                                                                                                      40
                                                           Storage Essentials
                                            Hard Drive Interface Technologies




SCSI Technology Overview
   SCSI (Small Computer System
    Interface) is a set of standards for
    physically connecting and
    transferring data between
    computers/ servers and peripheral
    devices.
   SCSI is commonly used for hard
    disks and tape drives, but can also
    be connected to a wide range of
    other devices, including scanners
    and CD drives.




                                                                                 41
                                                        Storage Essentials
                                                                Summary




Summary: Storage Essentials
   Hot spares are standby hard disk drives which are used as a backup
    to automatically replace a disk when a failure occurs. Spare count is
    the number of the hard disk drives provided as backup disks.
   Currently, there are many hard drive technologies being provided in
    the market which evolves from time to time. The most well known
    technologies are SATA, SCSI, Serial Attached SCSI (SAS), and Fiber
    Channel.
   SATA is the most commonly used technology today, especially at
    the end user level, e.g. computer device.
   SCSI was commonly used for hard disks and tape drives, but can
    also be connected to a wide range of other devices, including
    scanners and CD drives. Currently, SCSI is widely used on servers
    and not on the end user client devices.



                                                                             42
                                                                                   Storage Essentials
                                                                           Questions and Answers




Questions and Answers: Storage Essentials
1. What is the benefit of providing a spare disk?
     A.   To enlarge the storage capacity when all disks have been used to store data.
     B.   Ensure reliability by designating the spare disk as a standby/backup disk which will be used in
          case of disk failure.
     C.   To serve as additional disk for use when scheduled downloading is configured.
     D.   To serve as part of a RAID when configured, for example, to save mirrored data for RAID 1.

2. Select the hard drive type(s) which offer the key advantages of full bandwidth to each
   connected device, hot plug capability, smaller connector, standardized connector
   placement and layout, simpler cabling, and longer cable length. (Choose all that apply)
     A.   SCSI
     B.   SATA
     C.   iSCSI
     D.   PATA

3. What are the benefits of using SATA hard disks when compared to IDE hard disks?
   (Choose all that apply)
     A.   Master/Slave selection
     B.   Smaller cable connector
     C.   Speed
     D.   Hot-pluggable




                                                                                                            43
DCS – Storage

SAN Technologies


                   44
                                                      SAN Technologies




SAN Technologies




After this section, you should gain more knowledge of the following:
1. Technologies built for Storage Area Network
2. Details about FC SAN technologies and the required components to
   implement it on the network
3. Details about iSCSI technologies as well as its advantages and the
   required components to implement iSCSI on SAN

                                                                         45
                                                                           SAN Technologies
                                               Technologies lies behind the SAN




SAN Technologies Overview
   Technologies created for building a SAN are primarily based on either Fiber
    Channel or iSCSI technology.
   The next few pages explain each of these technologies in greater detail.

                                                  iSCSI Initiator    TCP/IP Protocol      iSCSI Target




                                                                    iSCSI Technology      D-Link SAN


                                                                      Ethernet Switch




                                                                        Private
                                                                     Local Network
                                                                                          D-Link SAN
                                                                          SAN

                                                           Copper / Optical cabling for iSCSI connection




                                                                                                           46
                                                                      SAN Technologies
                                                          Fiber Channel Technology




Fiber Channel Technology Overview
   Fiber Channel (FC) is a channel/network standard defined by the
    Technical Committee T11, which is the committee within INCITS
    (InterNational Committee for Information Technology Standards)
    responsible for Fiber Channel Interfaces
   FC network contains network features that provide the required
    connectivity, distance, and protocol multiplexing.
   Advantages of Fiber Channel*:
     •   Solutions leadership
     •   Reliable
     •   Fast data transfer providing gigabit bandwidth up to 4Gbps
     •   Multiple topologies
     •   Scalable
     •   Congestion free
     •   High Efficiency
     •   Full suite of services

     * The information is taken from Fiber Channel Industry Association
        (http://www/fibrechannel.org)
                                                                                         47
                                                                   SAN Technologies
                                                        Fiber Channel Technology




Basic Components of Fiber Channel SAN
   Storage devices supporting Fiber Channel
   Fiber Channel Switch (SAN fabric)
   Fiber Channel Host Bus Adapter (HBA)
   Cabling
                                     FC Host Bus Adapter           FC Storage Media




                 Public Local
                 Area Network
                                                 Fiber Channel
                                                    Switch


                                                       Private
                                                   Fiber Channel
                                                        SAN


                                        Optical cabling for fiber channel connection
                                                                                       48
                                                                       SAN Technologies
                                                    Hard Drive Interface Technologies




iSCSI Technology Overview
   Definition of iSCSI (Internet SCSI)
     • SCSI protocol which enables access to networked storage devices over
       a TCP/IP network (Ethernet network, WAN, Wireless network, etc)
   Why iSCSI? – iSCSI Features
     • Error Handling
          – Error checking using CRC (Cyclic Redundancy Check) methodology
          – When iSCSI detects errors it will bring down the session (all TCP connections
            within the session) and restart it
     • Boot
     • Discovery
   Advantages of iSCSI
     •   Connectivity over long distances
     •   Lower costs
     •   Easier implementation and management
     •   Built-in security

                                                                                            49
                                                                       SAN Technologies
                                                    Hard Drive Interface Technologies




Advantages of iSCSI over FC SAN
   iSCSI is a better alternative to Fiber Channel SAN for the following reasons:
     •   Built on stable and familiar standards providing easier implementation and
         management
     •   Ethernet transmissions can travel over the global IP network and therefore have no
         practical distance limitation
     •   Scalable                                          Source : IDC 2006 Sept./Dec.
     •   Creates a SAN with lower cost
     •   Interoperability issue
     •   Security issue




                                         According to IDC, iSCSI market grows with an
                                         explosive record of about 108.4% every year.
                                         According to IDC, by 2010, iSCSI products will
                                          share more than 21% of the storage market.
                                                                                              50
                                                                  SAN Technologies
                                                       Drive Interface Technologies




iSCSI SAN Overview
   iSCSI SAN components consist of:
                                                      Server
     •   iSCSI Client/ Host (iSCSI initiator)
          – A client device, for example, a server
            (or PC), which attaches to an IP                      iSCSI Initiator
            network
          – iSCSI Client initiates requests and
            receives responses from an iSCSI
            target
     •   iSCSI Target
          – A device that receives and processed                  TCP/IP Protocol
            the iSCSI commands, for example, a
            storage device




                                                                    iSCSI Target
                                                     D-Link SAN




                                                                                       51
                                                       SAN Technologies
                                                              Summary




Summary: SAN Technologies
   iSCSI is a network protocol which enables access to storage devices
    and network storage over TCP/IP networks.
   D-Link adopts the iSCSI protocol to be used in its D-Link SAN.
   iSCSI offers several benefits in comparison to Fiber Channel. These
    include interoperability, scalability, security, cost, and distance
    limitation.
   To implement iSCSI on the SAN, all the components must be
    provided: iSCSI initiator, iSCSI target, and Ethernet switch.




                                                                          52
                                                   SAN Technologies
                                              Questions and Answers




Questions and Answers: SAN Technologies
1. What are the components needed when deploying Fiber Channel
   SAN? (Choose all that apply)
   A.   SCSI Storage
   B.   Switch
   C.   Fiber Channel Switch
   D.   FC Host Bus Adapter


2. What component s not needed when deploying iSCSI?
   A.   Server
   B.   iSCSI target
   C.   Switch
   D.   Fiber Channel Switch




                                                                       53
DCS – Storage

D-Link SAN
(Storage Area Network)

                         54
                                                          D-Link SAN




D-Link SAN (Storage Area Network)




After this section, you should gain more knowledge of the following:
1. Various D-Link SAN appliances and differences between each
2. Each part of the hardware in the SAN
3. Key selling points of D-Link SAN appliances
4. Product positioning of D-Link SANs
5. D-Link SAN product interoperability, caching behavior, and common
   implementation architectures

                                                                       55
                                                       D-Link SAN
                       D-Link Products for Storage Area Network




D-Link Storage Area Network
   DSN-2100 Series        xStack Storage with 4-port 1GE Copper
    •   DSN-2100-10        for SATA-II Hard Drives in RAID Levels
                                 0, 1, 1+0, and 5 (8 Trays)


   DSN-3200 Series
                           xStack Storage with 8-port 1GE Copper
    •   DSN-3200-10        for SATA-II Hard Drives in RAID Levels
    •   DSN-3200-20              0, 1, 1+0, and 5 (15 Trays)




   DSN-3400 Series        xStack Storage with 1-port 10 GE Fiber
    •   DSN-3400-10        for SATA-II Hard Drives in RAID Levels
                                 0, 1, 1+0, and 5 (15 Trays)
    •   DSN-3400-20




                                                                    56
                                                                                             D-Link SAN
                                                                       Components of D-Link SAN




 Components of D-Link DSN-2100 Series
Front Panel Components
                                                  Front panel after the bezel has been removed
          Key lock
                                                                                        Eight drive bays


                                                              Power LED               Boot and Fault LED


  Latch        Removable Bezel

                                              Drive power LED Drive and Activity Fault LED

Back Panel Components

                            Diagnostic Port       Power Switch



   Host network                                                                   Power Supply
    connections


                                 Management Port     Reset Switch

                                                                                                           57
                                                                                             D-Link SAN
                                                                      Components of D-Link SAN




    Components of D-Link DSN-3200 Series
   Front Panel Components


Removable Bezel




                          Key lock

    Back Panel Components
                                                                              Power Supply
                                   Power Switch
                                                  Reset Switch




        Host Network Connections


                                            Diagnostic Port Management Port

                                                                                                          58
                                                                                              D-Link SAN
                                                                      Components of D-Link SAN




   Components of D-Link DSN-3400 Series
    Front Panel Components



Removable Bezel




                           Key lock

    Back Panel Components
                                                                               Power Supply
                                    Power Switch
                                                   Reset Switch




         Host Network Connections


                                             Diagnostic Port Management Port
                                                                                                           59
                                                                     D-Link SAN
                                                     Components of D-Link SAN




Management Port and Diagnostic Port
   Management Port
    • The management port is used to configure and manage D-Link‘s xStack
      SAN from the PC, either directly connected to the SAN (using a
      Crossover cable) or connected to the SAN through the use of a hub or
      switch (using Straight-through cable).
    • By connecting to this management port, the administrator can configure
      the D-Link SAN through the web GUI.
   Diagnostic Port
    • The diagnostic port is a console port which uses a RS-232-to-DB-9 port
      interface. This port can be used if you have direct physical access to the
      box and is accessed during startup.
    • The diagnostic port performs all admin password resets, sets the
      download configuration parameters, and accesses the Enclosure
      Services Test Tool.




                                                                                   60
                                                                     D-Link SAN
                                               D-Link DSN-2100 Series




DSN-2100 Series
Volume and RAID support
                                          Hardware Specification
• Single RAID Controller (Integrated
                                          • Drive Bays: 8
  in ASIC)
                                          • Drive Interface support: SATA-II
• RAID support (Level 0, 1, 1+0, 5)
                                          • Storage Capacity: 8TB capacity
• Supports 1,024 Virtual Volumes
                                            with 1TB hard drive
  (256 accessible per initiator)
                                          • System Memory: 256MB to
• 1,024 target nodes
                                            512MB (512MB standard)
• Online capacity expansion
                                          • Cache Memory: 256MB to 4Gb
• Hot swappable drives                      (512MB standard)
• Instant volume access                   • iSCSI Network Interface: four (4)
                                            1GbE ports
• Free space defragmentation
• Auto-detection failed drive
                                       iSCSI Network Interface
• Auto-rebuild spare drive
                                       • Host Interface: iSCSI Draft 2.0
• RAID level migration
                                         compliant initiator
• Drive roaming-in power off
                                       • Connections: 1,024 Hosts
• Self-Monitoring Analysis and
                                       • Jumbo Frames support
  Reporting Technology (S.M.A.R.T)
                                       • Link Aggregation support

                Storage Management     • CHAP authentication

                • Embedded IP-based    • Access control of management
                  Management GUI       • iSCSI/TCP/IP Full HW Offload
                • SMI-S version 1.1    • VLAN Support (Up to 8 VLANs)
                                                                                  61
                                                                 D-Link SAN
                                           D-Link DSN-3200 Series




DSN-3200 Series
                                       Hardware Specification
Volume and RAID support
                                       • Drive Bays: 15
• Single RAID Controller (Integrated
  in ASIC)                             • Drive Interface support: SATA-II
• RAID support (Level 0, 1, 1+0, 5)    • Storage Capacity: 15 TB capacity
                                         with 1TB hard drive
• Supports 1,024 Virtual Volumes
  (256 accessible per initiator)       • System Memory: 512MB
• 1,024 target nodes                   • Cache Memory: 4GB
• Online capacity expansion            • iSCSI Network Interface: eight (8)
                                         1GbE ports
• Hot swappable drives
• Instant volume access
• Free space defragmentation             iSCSI Network Interface
• Auto-detection failed drive            • Host Interface: iSCSI Draft 2.0
                                           compliant initiator
• Auto-rebuild spare drive
                                         • Connections: 1,024 Hosts
• RAID level migration
                                         • Jumbo Frames support
• Drive roaming-in power off
                                         • Link Aggregation support
• Self-Monitoring Analysis and
  Reporting Technology (S.M.A.R.T)       • CHAP authentication
                                         • Access control of management
               Storage Management        • iSCSI/TCP/IP Full HW Offload
               • Embedded IP-based       • VLAN Support (Up to 8 VLANs)
                 Management GUI
                                         • QoS support (IETF DiffServ and
               • SMI-S version 1.1         IEEE 802.1P tag)
                                                                              62
                                                                    D-Link SAN
                                              D-Link DSN-3400 Series




DSN-3400 Series
Volume and RAID support
• Single RAID Controller (Integrated      Hardware Specification
  in ASIC)                                • Drive Bays: 15
• RAID support (Level 0, 1, 1+0, 5)       • Drive Interface support: SATA-II
• Supports 1,024 Virtual Volumes          • Storage Capacity: 15 TB capacity
  (256 accessible per initiator)            with 1TB hard drive
• 1,024 target nodes                      • System Memory: 512 MB
• Online capacity expansion               • Cache Memory: 4GB
• Hot swappable drives                    • iSCSI Network Interface: one (1)
• Instant volume access                     10GbE ports

• Free space defragmentation
• Auto-detection failed drive          iSCSI Network Interface
• Auto-rebuild spare drive             • Host Interface: iSCSI Draft 2.0
                                         compliant initiator
• RAID level migration
                                       • Connections: 1,024 Hosts
• Drive roaming-in power off
                                       • Jumbo Frames support
• Self-Monitoring Analysis and
  Reporting Technology (S.M.A.R.T)     • CHAP authentication
                                       • Access control of management

             Storage Management        • iSCSI/TCP/IP Full HW Offload

             • Embedded IP-based       • VLAN Support (Up to 8 VLANs)
               Management GUI          • QoS support (IETF DiffServ and
             • SMI-S version 1.1         IEEE 802.1P tag)
                                                                               63   63
                                                                  D-Link SAN
                                      Market Analysis for D-Link SAN Products




Key Selling Points of D-Link SAN
   Block data transfer over TCP/IP network using iSCSI
   Highly integrated single chip solution
   Built-in RAID controller
   Built-in IP-SAN Device Manager (IDM)
   SATA-II support for the hard drive interface
   Various number of iSCSI interfaces which can be aggregated
   Jumbo Frame support increases performance up to 20-50%*




    * Based on information from Storage Networking Industry Association



                                                                                 64
                                                                                      D-Link SAN
                                                 Market Analysis for D-Link SAN Products




Product Positioning for D-Link SAN
   The D-Link xStack Storage product family of iSCSI SAN solutions
    are designed to address the growing high performance storage
    requirements brought about by the need for better application and
    database performance, infrastructure consolidation, and robust
    backup and disaster recovery solutions.
   D-Link now aggressively addresses these storage requirements at
    the SMB and enterprise level users by leveraging existing iSCSI and
    Ethernet technologies and lowering the total cost of ownership for
    storage area networking solutions over more complex legacy Fiber
    Channel and slower Network Attached Storage (NAS) solutions.
    • DSN-2100/ DSN-3200 comes with Gigabit Copper interfaces and is
      mainly targeted at SMB users.
    • DSN-3400 comes with 10-Gigabit Ethernet interfaces* and is mainly
      targeted for enterprise users.

       * DSN-3400 provides one 10GbE XFP transceiver interface (transceiver sold separately) accessed
       via the back panel.
                                                                                                        65
                                                             D-Link SAN
                                              D-Link SAN Implementation



Storage Interoperability – SMI-S Storage Device
   Storage Management Initiative – Specification (SMI-S) is a storage
    standard developed and maintained by Storage Networking
    Industry Association (SNIA).
   The main objective of SMI-S is to guarantee interoperability of
    storage devices among different vendors.
   D-Link‘s SAN series are all designed based on the standard SMI-S
    version 1.1.




                                                                           66
                                                             D-Link SAN
                                              D-Link SAN Implementation




Caching Operation
   The xStack storage unit contains cache memory for storing and
    data.
   The xStack storage unit is capable of caching write operations.
    Write-back caching saves the system from performing many
    unnecessary write cycles to the system RAM, so as to provide faster
    execution.




                                                                           67
                                                                      D-Link SAN
                                                   D-Link SAN Implementation




Basic iSCSI SAN Implementation
   In the most basic iSCSI SAN deployment, application servers (iSCSI hosts)
    access their storage from an iSCSI target storage array.

                                   iSCSI Host




      iSCSI Target




                                                                 ……
                     Private LAN                    Public LAN




                                                                                   68
                                                                   D-Link SAN
                                                                    Summary




Summary: D-Link SAN
   D-Link provides three series for its SAN appliance product line which
    include DSN-2100, DSN-3200, and DSN-3400 series.
   D-Link DSN-2100 provides eight drive bays while D-Link DSN-3000
    series provides 15 drive bays.
   Generally, all D-Link SANs must have the following components built in:
    host network connections, management port, diagnostic port, power
    and reset switch button, power supply, and removable bezel.
   D-Link SAN appliances are mainly targeted for SMB and enterprise level
    users who need better application and database performance,
    infrastructure consolidation, robust backup and disaster recovery
    solutions.
   D-Link SAN series is guaranteed to be interoperable with other storage
    appliances from different vendors because of its achievement for SMI-S
    standard.
   By default, all D-Link SANs will cache all write operations to prevent the
    storage from performing many unnecessary write cycles to the system
    RAM.

                                                                                 69
                                                                 D-Link SAN
                                                     Questions and Answers




Questions and Answers: D-Link SAN
1. What standard is used to guarantee the interoperability of storage
   devices among different vendors?
   A.   IEEE
   B.   iSCSI
   C.   SNIA
   D.   SMI-S


2. Which of the following statement describe D-Link SAN?
   A. D-Link SAN supports PAP authentication to provide secure access to the
      SAN.
   B. With D-Link SAN, using diskless server is possible because it can be
      booted form the iSCSI SAN.
   C. D-Link xStack storage cache memory for storing data and writing
      operations.



                                                                               70
DCS – Storage

SAN Product Features
Overview*
* All features are explained based on DSN-3000 Series.


                                                         71
                                           SAN Product Features Overview




SAN Product Features Overview




After this section, you should gain more knowledge of the following:
1. Tasks/activities that can be done by D-Link SAN
2. Link aggregation and VLAN features supported in D-Link SAN
3. TCP/IP offload engine
4. CHAP authentication
5. Volume virtualization
6. Auto-Detection failed drive and volume rebuild features

                                                                           72
                                                            SAN Product Features Overview
                                                                         Volume Management




Task
   The xStack Storage unit can automatically, or at the administrator‘s
    demand, perform activities that take time and consume the controller‘s
    resources.
   The administrator can control, to some degree, when tasks are to be
    performed. Any task can be suspended and resumed by the
    administrator. Some tasks can be cancelled and some can be scheduled
    on a recurring, periodic interval.
   All tasks can have their priority changed, which controls the amount of
    resources the xStack storage unit devotes to a task.
   The tasks/ activities that can be done by D-Link‘s SAN are as follows:
   Volume initialization
   Volume rebuild*
   Volume expansion
   Media scanning
   Parity scanning

    * Volume rebuild will be explained later along with explanation of auto-detecting failed drive

                                                                                                     73
                                             SAN Product Features Overview
                                                       Volume Management




Volume Initialization
   Some volume organizations (e.g. parity) require initialization. The
    initialization task performs this action. This task can be performed
    while an initiator is accessing (reading and writing) data. An
    initialization task can be suspended and resumed, but cannot be
    cancelled.
   Initialization task consists of:
     • Making the volume XOR consistent
     • Detecting a read error
     • Recovering from read error




                                                                             74
                                                      SAN Product Features Overview
                                                                Volume Management




     Volume Expansion
        All D-Link SAN product series provide volume expansion to flexibly resize a
         logical drive.

          The Volume-1 has been
          resized to a bigger size



                   100GB


               300GB       Current size: 200GB
               200GB

                            Expand to 300GB

              Volume-1




Page is Animated                                                                       75
                                                SAN Product Features Overview
                                                           Volume Management




Parity Scanning
   D-Link SAN provides parity volume scanning to check errors found in that
    selected volume.
   This task reads every block in the volume to ensure parity is correct. If
    parity errors are found, this task corrects the errors.




                                                                                76
                                                             SAN Product Features Overview
                                                                      Volume Management




Storage Volume Information
   Storage volume information provides comprehensive information about the
    storage volume allocation
   Information that can be viewed in the storage volume information are:
     •   Status of the attached drives (offline or online)
     •   Volume Capacity
     •   Volume type




                                                                                             77
                                                SAN Product Features Overview
                                                           Device Management




Event Log
   The event log tracks the xStack Storage‘s information, warning, and error
    messages.




                                                                                78
                                                       SAN Product Features Overview
                                                                          iSCSI Features




Link Aggregation
   Definition of Link Aggregation:
     •   Link aggregation is a way to achieve double data rates by aggregating multi
         physical links as one logical link.
   Key benefits of Link Aggregation (LAG):
     •   Improved performance
     •   High data rates
     •   Increased availability
     •   Load sharing




                                                                                            79
                                           SAN Product Features Overview
                                                          iSCSI Features




Virtual LAN (VLAN)
   All D-Link Storage Area Networks support 802.1Q VLAN tagging to
    segregate traffic into isolated zone for more secure access and to
    segment the broadcast domain.
   D-Link SAN supports up to eight VLANs with 1-to-1 mapping
    between IP subnet and VLAN. Multiple VLANs per physical port with
    VLAN tag. All physical ports in LAG belong to same VLAN.
   With this feature, a volume can be configured under a VLAN group
    so that it will only be accessible by clients under the same VLAN.




                                                                            80
                                                SAN Product Features Overview
                                                                iSCSI Features




TCP/IP Offload Engine (TOE)
   The major issue of IP storage is the high TCP/IP processing overhead, which
    constrains servers to performance levels that are unacceptable for block
    storage transport.
   TCP/IP Offload is used for reducing the amount of TCP/IP processing
    handled by the microprocessor and I/O subsystem to help ease server
    networking bottleneck.




                                                                                  81
                                             SAN Product Features Overview
                                                             iSCSI Features




CHAP Authentication
   Challenge Handshake Authentication Protocol (CHAP) is a protocol
    for authenticating peer-to-peer connection based on the sharing of
    a ‗secret‘ known only to the authenticator and that peer.
   CHAP authentication is supported in all D-Link SAN product series
    and is used when an initiator tries to connect to its target, and vice
    versa.
   Characteristics of CHAP authentication:
   Unidirectional/ Bidirectional authentication
   Secret key is encrypted/ hashed using MD5 algorithm
   Three way handshake authentication




                                                                               82
                                            SAN Product Features Overview
                                                 Volume and RAID Support




Volume Virtualization
   D-Link xStack storage virtualizes disk storage for use by a
    customer's host computer (servers).
   Storage virtualization is the process of grouping together
    independent storage devices found across a network to create what
    seems to be a single large storage entity that can be centrally
    managed.
   Storage virtualization helps make the tasks of backup, archiving,
    and recovery easier, and in lesser time, by disguising the actual
    complexity of the SAN.
   Benefits of virtualization:
    • High availability
    • Improve capacity utilization
    • Share resources between heterogeneous servers




                                                                            83
                                                 SAN Product Features Overview
                                                       Volume and RAID Support



Auto-Detection of Failed Drive & Volume Rebuild
   When a drive in the storage array fails, the xStack storage will
    automatically detect the failed drive and substitutes it with the hot
    spare drive.
   A spare drive is normally kept in the available pool, so that the
    drive will be available for use should another drive fails.
   Volume rebuild is the activity that recovers data of a failed drive.
   In this case, data can be rebuilt if the storage system is mirrored
    (RAID 1) or set for parity (RAID 5).
     • If the storage is mirrored, data will be recovered from the mirrored data
       in the mirror disk.
     • If parity is created, data inside the failed drive will be recovered using
       the existing data from active disks and the parity information.




                                                                                    84
                                                            SAN Product Features Overview
                                                                   Volume and RAID Support




     Drive Roaming
        D-Link SAN provides feature for safely moving drive in an array .
        If a drive in an array configured with RAID is accidentally removed, the
         removed drive can still be recognized using this feature, as long as the drive
         is configured with RAID that provides fault tolerance (RAID 1 and RAID 5).
         This is known as drive roaming in power off.


            Array configured with RAID 1

                    Drive-0     Drive-1    Steps to move the drives safely:
                                           • Turn off the array in which the removed drive belongs to
                      1            1       • Plug the removed drive to any slot in the array
                                           • Reboot the array
                      2            2

                      3            3




                   Removed


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                                            SAN Product Features Overview
                                                 Volume and RAID Support



Self Monitoring and Reporting Technology
(S.M.A.R.T)
   D-Link SAN Series support Self-Monitoring Analysis and Reporting
    Technology (S.M.A.R.T.), a technology designed to monitor the
    reliability of hard drives.
   The purpose of S.M.A.R.T. is to warn a user or system administrator
    of impending drive failure while time remains to take preventative
    action — such as copying the data to a replacement device.
   Features of S.M.A.R.T. technology include a series of attributes, or
    diagnostics, chosen specifically for each individual drive model.
    Attribute individualism is important because drive architectures vary
    from model to model.




                                                                            86
                                                   SAN Product Features Overview
                                                                          Summary




Summary: SAN Product Features Overview (1)
   The xStack Storage unit can automatically, or at the administrator‘s demand,
    performs activities such as volume initialization, volume rebuild, volume
    expansion, media scanning, and parity scanning.
   Volume initialization is performed when an initiator (i.e. server) is reading or
    writing data.
   With D-Link SAN, the size of a volume can be flexibly expanded up to the
    maximum capacity of a storage.
   Media scanning provided in the management console of all D-Link SAN products
    can be used to scan a JBOD, stripe, mirrored stripe, or mirrored stripe media
    volume for errors.
   D-Link SAN provides parity volume scanning to check errors found in the selected
    volume.
   Task Manager provides general information for all task activity running on the D-
    Link SAN.
   Storage pool information provides comprehensive information about the storage.
   D-Link xStack Storage series accommodate a 6-cell shrink-wrapped battery pack
    for backing up the buffer cache contents in case of power failure.
   D-Link SAN provides an event log feature that tracks the xStack Storage
    informational, warning, and error messages
   To increase the data transfer performance and prevent bottleneck from occurring,
    D-Link SAN is provided with link aggregation feature to double the speed
    performance, depending on the number of the aggregated links.

                                                                                        87
                                               SAN Product Features Overview
                                                                    Summary




Summary: SAN Product Features Overview (2)
   All D-Link Storage Area Networks support 802.1Q VLAN tagging to
    segregate traffic into isolated zone for more secure access.
   TCP/IP Offload is used to reduce the amount of TCP/IP processing
    handled by the microprocessor and I/O subsystem to ease server
    networking bottleneck.
   CHAP authentication provides secured and encrypted authentication
    mechanism, and is supported in all D-Link SAN product series. It is used
    when an initiator tries to connect to its target, and vice versa.
   D-Link xStack storage virtualizes disk storage for use by a customer's
    host computer (servers) by grouping all storage devices found across a
    network to become a single large storage entity that can be centrally
    managed.
   When a drive in the storage array fails, xStack storage will
    automatically detect the failed drive and substitute the failed drive with
    the hot spare drive.
   S.M.A.R.T. is a technology supported in D-Link SAN series to monitor
    the reliability of hard drives and to warn a user or system administrator
    of impending drive failure while time remains to take preventative
    action

                                                                                 88
                                                        SAN Product Features Overview
                                                                 Questions and Answers



Questions and Answers:
SAN Product Features Overview
1. What tasks can be done by D-Link Storage Area Network? (Choose all that apply)
    A.   Volume Initialization
    B.   Media Scanning
    C.   Volume Rebuild
    D.   Error Correction
    E.   Volume Shrinkage

2. What cannot be done when an administrator expands a volume and initializes a
   grow task?
    A.   Grow task deletion
    B.   Grow task suspension
    C.   Grow task resumption
    D.   All of the above can be done when a grow task is initialized

3. What is the function of TCP/IP Offload Engine in D-Link SAN
    A. To bypass requests coming from the client over the network when the storage‘s
       CPU is high
    B. To turn off the xStack storage when it detects the TCP/IP utilization is high
    C. To safely move drive in an array by turning off the unit
    D. To reduce the amount of TCP/IP processing handled by the microprocessor and
       I/O subsystem

                                                                                          89
                                                    SAN Product Features Overview
                                                            Questions and Answers



Questions and Answers:
SAN Product Features Overview
4. What is the function of disk virtualization provided by D-Link SAN?
    A. To link multiple storage repositories to multiple clients and servers.
    B. To group all storage devices found across a network to become a single large
       storage entity that can be centrally managed
    C. To create storage clustering that comprises master storage and slave
       storage, where the slave serves as a backup of the master
    D. To achieve double data rates by aggregating multi physical links as one
       logical link.

5. What is the benefit of S.M.A.R.T.?
    A. Repair failed disk automatically by doing some diagnoses, analyze the main
       cause of the error, and perform reparation process depends on the analysis
       result.
    B. Provides 100% guarantee of disk failure prevention by regularly predicting
       each disk condition and provides maintenance to keep each disk in a good
       condition.
    C. Failure anticipation by regularly monitor all hard disks and report on various
       indicators of reliability, with the hope of anticipating failures.
    D. All of the above.
                                                                                        90
DCS – Storage

D-Link Network Attached
Storage (NAS)

                          91
                                   D-Link Network Attached Storage (NAS)




D-Link Network Attached Storage (NAS)




After this section, you should gain more knowledge of the following:
 Various D-Link NAS appliances and differences between each of
   them
 Key selling points of D-Link NAS appliances
 Functions and applications of D-Link NAS
 Product positioning of D-Link NAS

                                                                           92
                              D-Link Network Attached Storage (NAS)
                        D-Link Products for Network Attached Storage




D-Link Network Attached Storage (NAS)
DNS-313     • 1 Bay SATA Network Storage Enclosure
            • Built-in iTunes, UPnP and FTP Server
            • May be used as USB 2.0 portable hard drive (become a DAS
              enclosure)
DNS-321     • 2 Bays SATA Network Storage Enclosure
            • RAID 1 support
            • Built-in iTunes, UPnP and FTP Server


DNS-323     • 2 Bays SATA Network Storage Enclosure
            • RAID 1 support
            • Built-in iTunes, UPnP, and FTP Server
            • USB port for connecting to printer
DNS-343     • 4 Bays STA Network Storage Enclosure
            • RAID 1, 5 support
            • Multi-Functional USB port




                                                                         93
                                                          D-Link Network Attached Storage (NAS)
                                                D-Link Products for Network Attached Storage




D-Link DNS-313
                                                                             Device Interface
                                                                             • 1 Gigabit Ethernet port
                                                                             • 1 USB 2.0 port*
 Features
 • iTunes and UPnP AV server
 • Scandisk feature
 • Real-time backup
 • Email alerts                                                               Supported Hard Drive Type
 • Permission settings for user                                               • One 3.5-inches SATA
   and group                                                                    Standard Drive with capacity
 • Multi-language file name                                                     support up to 1.5 TB
   support
 • Scheduled downloads from
   web or FTP sites
 • Can be used as a USB 2.0
   portable hard drive
                                                                          Networking Features
                                                                          • DDNS
                                                                          • FTP
                                                                          • DHCP Server/ Client
                                                                          • NTP
                                                                          • HTTP/ HTTPS
                                                                          • CIFS/SMB

  *USB port is used for connecting to a desktop or notebook as a USB2.0 portable drive.
                                                                                                               94
                                          D-Link Network Attached Storage (NAS)
                                     D-Link Products for Network Attached Storage




D-Link DNS-321
Drive Management                                       Device Interface
• Multiple hard drive                                  • 1 Gigabit Ethernet port
  configurations (RAID 0, RAID 1,
  JBOD, Standard)
• iTunes and UPnP AV server
• Scandisk feature
• User/ group Quota Management
                                                          Supported Hard Drive Type
• File Sharing
                                                          • Two 3.5-inches SATA
• Support RAID migration (non-
                                                            Standard Drive with capacity
  RAID to RAID 1)
                                                            support up to 1.5 TB




                                                     Networking Features
                                                     • DDNS
    Device Management
                                                     • FTP / FTP over SSL/TLS
    • Email Alerts
                                                     • DHCP Server/ Client
    • Power Management
                                                     • NTP
    • Easy Search Utility
                                                     • HTTP/ HTTPS
    • Multilingual support
                                                     • CIFS/SMB
                                                     • Jumbo Frames



                                                                                           95
                                                             D-Link Network Attached Storage (NAS)
                                                   D-Link Products for Network Attached Storage




D-Link DNS-323
                                                                           Device Interface
                                                                           • 1 Gigabit Ethernet port
                                                                           • USB port*

Features
• 4 different hard drive
  configurations (Standard,
  JBOD, RAID 0, RAID 1)
• iTunes and UPnP AV server                                                       Supported Hard Drive Type
• Scandisk feature                                                                • Two 3.5-inches SATA
• Email alerts                                                                      Standard Drive with capacity
• Power management                                                                  support up to 1.5 TB
• Supports BitTorrent
• USB port supports UPS
  monitoring and Print Server
• Support RAID migration (non-
  RAID to RAID 1)                                                        Networking Features
                                                                         • DDNS
                                                                         • FTP / FTP over SSL/TLS
                                                                         • DHCP Server/ Client
                                                                         • NTP
                                                                         • HTTP/ HTTPS
                                                                         • CIFS/SMB
                                                                         • Jumbo Frames

*The USB port provided on D-Link DNS-323 is used to connect to the print server only
                                                                                                                   96
                                      D-Link Network Attached Storage (NAS)
                                 D-Link Products for Network Attached Storage




D-Link DNS-343
  Drive Management                                Device Interface
  • Multiple hard drive                           • 1 Gigabit Ethernet port
    configurations (RAID 0,                       • 1 USB 2.0 port
    RAID 1, RAID 5, JBOD,
    Standard)
  • iTunes and UPnP AV server
  • Scandisk
  • User/ group Quota
                                                      Supported Hard Drive Type
    Management
                                                      • Four 3.5-inches SATA
  • File Sharing
                                                        Standard Drive with capacity
                                                        support up to 1.5 TB




  Device Management
                                                 Networking Features
  • UPS Monitoring
                                                 • Jumbo Frame
  • Email Alerts
                                                 • DDNS
  • Power Management
                                                 • FTP / FTP over SSL/TLS
  • Easy Search Utility
                                                 • DHCP Server/ Client
  • Multilingual support
                                                 • NTP
  • ADS support
                                                 • HTTP/ HTTPS
  • Auto Power Recovery
                                                 • CIFS/SMB



                                                                                       97
                                                         D-Link Network Attached Storage (NAS)
                                                    D-Link Products for Network Attached Storage




OLED – Special Display on D-Link DNS-343
   Organic Light-Emitting Diode (OLED) is a LED screen that displays
    information to enable the administrator to easily view and obtain the status
    and basic information of the DNS-343
   Information that can be viewed from the OLED include:
     •   System Information
          –   Hostname of the DNS-343
          –   Firmware version
          –   IP address of the DNS-343
          –   Operating temperature
     •   Hard Drive Status
          – Space percentage used on the hard disk
     •   Server Status
          –   Status   of   the   printer server
          –   Status   of   the   UPnP AV server
          –   Status   of   the   iTunes server
          –   Status   of   the   FTP server




                                                                                                    98
                                    D-Link Network Attached Storage (NAS)
                                   Market Analysis for D-Link NAS Products




Key Selling Point of D-Link NAS
   File-sharing across the local network and Internet using FTP and
    HTTPS
   Flexible options for array capacity, supporting up to 1.5TB
   Easy installation
   Users and Groups/Folder with Quota and permission rights (read/
    write) management
   Appliance servers for network users (printer server, UPnP AV
    server, etc)
   iTunes automatic discovery of music stored on the NAS
   Peer to Peer download client support




                                                                              99
                                                        D-Link Network Attached Storage (NAS)
                                                       Market Analysis for D-Link NAS Products




  D-Link NAS Functions and Applications
     Shares and backup files from                          Connects to UPS for monitoring
      multiple clients                                       function
     Remote access via FTP                                 Downloads shared files from the
     Streams music, photos, and videos                      Internet using BitTorrent
      from the NAS to a media player                        Stores recorded video surveillance
     Shares printer on the LAN                              directly




                                                                    (FTP: port 21)     Obtains files stored in NAS
                                                                                           Remote Client
                        (P2P Connection)
                                                                        (UPnP AV)

                                            Connects through USB port

Download shared file using P2P connection

                                           UPS
                                                                 Printer
                                                                                    D-Link Multimedia Player   100
                                    D-Link Network Attached Storage (NAS)
                                    Market Analysis for D-Link NAS Products




Product Positioning for D-Link NAS
   D-Link NAS products are suitable for home user, SOHO and SMB
   D-Link Network Storage Enclosures address the ever-growing data
    storage requirements for multimedia and large data files for small
    to medium business users
   Need for data consolidation and data sharing make this enclosure
    an ideal solution
   Various RAID level support offers advanced data protection
   This versatile enclosure supports the latest SATA technology and
    Gigabit Ethernet connectivity for best-in-class performance




                                                                           101
                                    D-Link Network Attached Storage (NAS)
                                                               Summary



Summary: D-Link Network Attached Storage (NAS)
   D-Link provides four main models for its NAS appliance product
    line: DNS-313, DNS-323, DNS-321, and DNS-343.
   All D-Link NAS appliances can be used to act as an iTunes server,
    UPnP server, FTP server, printer server, and for certain models, D-
    Link also supports added networking features such as a DHCP
    server, and advanced features such as quota management and
    DDNS, etc.
   D-Link DNS-343 provides an added feature on the box, which is an
    OLED screen to show certain status information, such as system
    information, hard drive status, and the server appliance status.
   D-Link NAS appliances are primarily targeted at home users, SOHO,
    or SMB users who want the benefits of network storage that is cost
    effective.



                                                                          102
                                          D-Link Network Attached Storage (NAS)
                                                           Questions and Answers



Questions and Answers:
D-Link Network Attached Storage (NAS)
1. Which model of D-Link NAS provides OLED screen feature on the box?
    A.   DNS-313
    B.   DNS-323
    C.   DNS-321
    D.   DNS-343

2. What are the functions of D-Link NAS? (Choose all that apply)
    A.   Easy RAID migration and adaptability
    B.   Play music from iTunes software with the music stored in NAS
    C.   Stream music, photos and videos to a media server
    D.   Wireless access of data in the NAS via wireless client

3. Which RAID features are supported by D-Link DNS-323? (Choose all
   that apply)
    A.   RAID   0
    B.   RAID   1
    C.   RAID   5
    D.   RAID   10


                                                                                103
DCS – Storage

NAS Product Features
Overview*

*All features are explained based on the DNS-343 product
                                                           104
                                            NAS Product Features Overview




NAS Product Features Overview
After this section, you should gain more knowledge of the following:
1. What is the Easy Search Utility and the functions supported in this
    feature
2. What is the Configuration Wizard and what configuration tasks are
    available to this wizard
3. What is Email Alerts
4. The characteristics of power management on D-Link NAS
5. Function of Disk Diagnostic feature
6. Purpose of user and group creation on D-Link NAS
7. The function of quota management
8. Appliance server roles with/without the use of USB port on D-Link NAS
9. Remote Backup
10. Peer-2-Peer (P2P) Downloads
11. Volume/File sharing on D-Link NAS and scheduled downloading

                                                                           105
                                         NAS Product Features Overview
                                                  Managing the Device




Easy Search Utility
   Easy Search Utility is provided to
    help the users find the D-Link NAS
    on the network.
   What D-Link Easy Search Utility
    can:
   Discover and connect to D-Link
    NAS products.
   Map drives
   Configure the IP of the NAS




                                                                     106
                       NAS Product Features Overview
                                Managing the Device




Configuration Wizard




                                                   107
                                                   NAS Product Features Overview
                                                              Managing the Device




Email Alerts
   With the email alerts feature supported in the D-Link NAS product series,
    alerts can be sent to a specified user if certain operational conditions occur,
    such as the following:
     •   Information about space status
     •   A volume is full
     •   A hard drive has failed
     •   Administrator password has been
         changed
     •   Firmware has been upgraded
     •   System temperature has exceeded
         the specified temperature*




                                                                                      108
                                                 NAS Product Features Overview
                                                            Managing the Device




Power Management on D-Link NAS
   Power management offers a green feature on D-Link NAS products.
   With this feature, the administrator can configure the drives to shut down
    after a specified idle time. The device will automatically power up when data
    is being accessed by the client.




                                                                                    109
                                                   NAS Product Features Overview
                                                               Managing the Device




Disk Diagnostic
   Scandisk activity can be performed to check if any error has occurred on the
    hard disk.
   With this feature, all errors found will be listed with a description, along with
    the option to repair each of these errors.
   Scandisk can be performed over selected volume.




                                                                                        110
                                           NAS Product Features Overview
                                             User and Group Management




User and Group Creation
   User and groups can be created
    and managed on the D-Link NAS
    product series.
   The purpose of creating users and
    groups on the NAS product is to
    control user access to the storage
    and to control read/write privileges
    for specified folders on the network
    drives, or to setup FTP access
    rights.




                                                                       111
                                                 NAS Product Features Overview
                                                   User and Group Management




Network Access
   The Network Access feature is used to assign access rights to a user or a
    group for specific folders or volumes.




                                                                                112
                                                 NAS Product Features Overview
                                                    User and Group Management




Quota Management
   The D-Link NAS product series supports quota management for groups,
    folders, and individual users.
   Assigning quotas to a groups, folders, or users will limit the amount of
    storage capacity allocated for them.




                                                                               113
                                   NAS Product Features Overview
                                         User and Group Management




     Quota Illustration

                          Volume-1
                                               Saving Data Failed!!!
                                      Data saved!!! Current for Robert is 1GB
                                     Current available space available space for
                                                             100MB
                                                   Robert is 400MB
                                                Quota Exceeded!!!




                           D-Link NAS

                             Saves
                          600MB data
                          200MB
                          300MB
                          to volume-1


                                         Robert

                            Quota limit for Robert is 1GB




Page is Animated                                                                   114
                                                NAS Product Features Overview
                                                             Appliance Servers




FTP Server
   The D-Link NAS product series are equipped with a built-in FTP Server. With
    this feature, data resources kept in the NAS can be accessed via FTP, both
    from the inside and outside network.




                                                                                  115
                                                NAS Product Features Overview
                                                             Appliance Servers




UPnP AV Server
   UPnP (Universal Plug and Play) is a set of network protocols that allows
    devices to connect seamlessly and to simplify the implementation of
    networks in the home digital environment (data sharing, communications,
    and entertainment) and/or corporate environments.
   UPnP AV (Audio and Video) servers store and share digital media, such as
    photographs, movies, and music to provide hardware-based media
    streaming services to UPnP AV compatible clients on the local network.




                                                                               116
                                                  NAS Product Features Overview
                                                               Appliance Servers




iTunes Server
   D-Link NAS comes with a feature in which end users can listen to music
    from iTunes at their own desk with the music files stored in the NAS.
   With this feature, the iTunes software will automatically detect the folder
    specified by the administrator. Therefore the administrator must specify a
    folder that contains a collection of songs stored on the NAS.




                                                                                  117
                                  NAS Product Features Overview
                                                     Appliance Servers




iTunes at the Client Side
 Song library stored on the D-
   Link NAS is automatically
  detected using the iTunes
 application on the client side




                                      D-Link NAS




                                      iTunes server
                                   feature is activated
                                    on the D-Link NAS


                                   Play music from the
                                     NAS with iTunes

                                                                      118
                                                     NAS Product Features Overview
                                                                 Networking Features




DDNS
   Dynamic DNS (DDNS) allows the hosting of a server using a domain name
    assigned with a dynamic IP address.
     •   DDNS helps to deal with servers publishing IP addresses that constantly change
         due to the use of dynamic IP addresses.
     •   In the D-Link NAS product series, the DDNS feature can be used to make the NAS
         accessible from a public network.

   D-Link provides a utility for
    customers to use the DDNS service
    provided by www.dlinkddns.com
    (only 1 host may be created using
    the D-Link DDNS service).
   Free DDNS service can also be
    obtained from www.dyndns.com.




                                                                                          119
                                               NAS Product Features Overview
                                                          Networking Features




Remote Backup
   The D-Link NAS Remote Backup allows you to backup the files stored on the
    NAS to one or more remote NAS devices in order to prevent data loss in the
    event of a failure.




                                                                                 120
                                                NAS Product Features Overview
                                                          Networking Features




Peer-2-Peer (P2P) Download
   The D-Link NAS P2P Downloads allows the user to share files and folders via
    torrents. This is a great way to share files with friends, colleagues, and
    family.




                                                                                  121
                                                       NAS Product Features Overview
                                                                   Networking Features




File Sharing
   D-Link NAS provides two ways to share files to all users over the
    network
   Samba
     • Samba is an Open Source/Free Software suite that provides seamless
       file and print services to SMB/CIFS clients and allows interoperability
       between Linux/Unix servers and Windows-based clients.
     • FTP
   For file sharing, D-Link also provides multilingual support for the
    local user to easily share files without any difficulties.
     • Samba: Unicode
     • FTP Client:
         – Croatian, Cyrillic (Kyrgyz Republic), Czech, Danish, Dutch, English, Finnish,
           French, German, Greek, Hungarian, Italian, Japanese, Korean, Norwegian,
           Polish, Portuguese, Romanian, Russian, Simplified Chinese, Slovenian,
           Spanish, Swedish, Traditional Chinese, Turkish.



                                                                                           122
                                               NAS Product Features Overview
                                                         Networking Features




Scheduled Downloading
   The D-Link NAS Download Scheduling feature allows the administrator to set
    up a schedule for downloading folders or files, and backup sessions.




                                                                                 123
                                               NAS Product Features Overview
                                                           USB Port Applications




Print Server
   The D-Link NAS can be directly connected to a printer to make the NAS
    become a print server.




                                               Printer attached to the NAS can
                                               be accessed from the client side



                                                                                  124
                                                NAS Product Features Overview
                                                         USB Port Applications




UPS Monitoring
   An Uninterruptible Power Supply (UPS) can be directly connected to a D-Link
    NAS through the provided USB port.
   The purpose of attaching the UPS to the NAS is to provide a way to safely
    shutdown the NAS in case of a power failure.
   When a UPS (Uninterruptible Power Supply) is connected to the NAS, the
    Status screen hides the printer information and displays information about
    the UPS (such as, the manufacturer, product type, battery power status,
    and UPS status).




                                                                                  125
                                              NAS Product Features Overview
                                                                  Summary




Summary: NAS Product Features Overview (1)
   The Easy Search Utility is a feature in D-Link NAS that helps make the
    administrator's task easier by displaying all the D-Link NAS products
    found within the subnet. Besides providing NAS discovery, it can also be
    used to map drives and configure IP addresses.
   To make device configuration easier, D-Link NAS provides a
    configuration wizard to perform the basic configuration of the device.
    This is useful for some users who are unfamiliar with configuring the
    device.
   Email alerts is a feature which warns a specified user, usually the
    administrator, when certain conditions, as specified by the
    administrator, are encountered.
   Power management is a feature designed to help cut down on the
    energy used by the NAS. With this feature the D-Link NAS will
    automatically shutdown after being idle for some specified amount of
    time.
   D-Link provides the Disk Diagnostic feature which can be used to
    perform error checking on a disk. This is to ensure the integrity of the
    data stored on the disk.
   Users and groups can be created and managed on the D-Link NAS to
    better control user access to the data stored on the NAS. Quotas can
    also be applied to users/groups/folders.
                                                                               126
                                              NAS Product Features Overview
                                                                  Summary




Summary: NAS Product Features Overview (2)
   All D-Link NAS can be set to act as application servers serving
    added functionality to its clients, such as to act as an iTunes server,
    UPnP server, FTP server, and print server.
   Dynamic DNS (DDNS) is a feature which can be used to host a
    server using a dynamic IP address by giving the host a domain
    name so it is accessible by the public.
   With a NAS appliance, file sharing over the network becomes much
    easier by sharing a volume all at once using the drive mapping
    feature. File sharing can also be done by using FTP or Samba.
   The D-Link NAS appliance can be instructed to perform scheduled
    downloading from a specified URL.
   An Uninterruptible Power Supply (UPS) can be connected to a D-
    Link NAS through the provided USB port to provide a safe shutdown
    after a power failure.


                                                                              127
                                                                  NAS Product Features Overview
                                                                             Questions and Answers



Questions and Answers:
NAS Product Features Overview
1. What is the function of the Easy Search Utility feature?
     A.   To   search for files stored in the D-Link NAS based on keywords or file extensions.
     B.   To   find errors that have occurred on the D-Link NAS.
     C.   To   discover D-Link NAS products over the network.
     D.   To   search the activity history saved on the D-Link NAS.

2. What feature on D-Link NAS is used to check errors that have occurred in the hard
   disk?
     A.   Scan Disk
     B.   Media Scanning
     C.   Parity Scanning
     D.   Disk Scanning

3. How many concurrent users are allowed to access FTP in D-Link NAS?
     A.   1
     B.   4
     C.   10
     D.   Unlimited

4. What are the purposes of USB port provided in D-Link NAS? (Choose all that apply)
     A.   To   make the NAS become a print server if connected to a printer from the USB port.
     B.   To   connect to iPod to synchronize music from the iPod to the NAS.
     C.   To   connect to a USB scanner so it can scan a file directly.
     D.   To   connect to a UPS to enable a safe shut down upon power failure.
                                                                                                  128
                                                  NAS Product Features Overview
                                                           Questions and Answers



Questions and Answers:
NAS Product Features Overview
5. What feature must be used to publish a D-Link NAS for public access when it is
   assigned a dynamic IP address rather than a static IP address?
    A.   DNS
    B.   FTP Server
    C.   D-Link UPnP AV Server
    D.   DDNS

6. What are the appliance server functions supported by D-Link NAS? (Choose all
   that apply)
    A.   iTunes Server
    B.   DNS Server
    C.   FTP Server
    D.   Web Server
    E.   UPnP AV Server

7. What is the method used to share files on the D-Link NAS if using remote access?
    A.   DNS
    B.   FTP
    C.   Telnet
    D.   SSH


                                                                                      129
DCS – Storage

Applications and Solutions
for Network Storage

                             130
                             Applications and Solutions for Network Storage




Applications and Solutions for Network Storage




After this section, you should gain more knowledge of the following:
1. NAS application for sample reference
2. SAN application for sample reference

                                                                          131
                                   Applications and Solutions for Network Storage
                                                                           NAS Applications




NAS Application for SMB Environment



         Wireless LAN
                                                              Wired LAN
                                        Wireless
                                        Router
    Guest-1
           Wireless Clients
                                                                            Employee-1

     Guest-2                            DNS-343

                                                              Employee-2


                                                   Printer is shared by the NAS, therefore
                                                      can be accessed over the network


          The USB port can be attached to a UPS or USB Printer



                                                                                             132
                                      Applications and Solutions for Network Storage
                                                                            SAN Applications




SAN Application for Server Clustering
   Server clustering is a group of servers running the same application as a
    single virtual server.
   Server clustering prevents a single point of failure. If a server is goes down,
    another server will replace it and take the role of the primary server.
   In this scenario, the clustered servers share the same disks in the SAN.
                             Goes to Public Network




                  Clustered Email Servers   Clustered ERP Servers



                                                                    Tape Libraries




                                                    iSCSI SAN
                                                                                            133
                                            Applications and Solutions for Network Storage
                                                                                 SAN Applications




SAN Application for Monitoring Purposes
               Video Server with              Recorded videos from all cameras are stored
                 iSCSI initiator                     directly into the SAN storage




                                   Gigabit Ethernet Switch
                                                                                            SAN Storage



Wired Video Cameras                Links are aggregated
                                                                                        Backup Storage
                           Gigabit Ethernet Switch



  Wireless Camera


              D-Link Wireless N Router
                                                                 Video Post
                                                                 Processing
   Wireless Camera                                                 Server


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