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					An Open Source approach to replication and recovery.
Current Challenges:
 Miniscule IT Budgets.
 Backup Tapes don’t meet capacity needs or are costly.
 Most RAIDs don’t protect from certain data loss.
 Quick recovery of virtual disks and OS.
 Stuck with same vendor for offsite storage.
Vendor Specific Solutions
 Costly; upwards of $60,000 for infrastructure.
 Offers features only available to like systems.
 Choose Two out of Three: Fast, Reliable, Cheap.
 Yearly support costs can damper most IT budgets.
 Typical useable storage capacity: 2.8TB with a single
  shelf, the rest for snapshots and filesystem overhead.
An Open Source Solution
 Open Solaris with ZFS and iscsitarget software.
 Relatively inexpensive compared to 3rd party vendors
 Can mix and match hardware.
 ZFS: Virtually unlimited capacity!
 Technical creativity when building scripts.
Cons about Opensolaris iSCSI
 Not supported by VMware. (yet)
 OS and Filesystem Learning curve
 Limited to 1gb/s of bandwidth per SAN* (until 10gb/s
  is released)
 No support for MTU 9000 (Jumbo Frames)
Necessary Tools for success.
   ZFS File System; /sbin/zpool and /sbin/zfs; snapshots
   Iscsitadm (pkg add)
   SSH keygen/pgp
   A replication script (e.g.
   Cron
   Mail
   Enable Vmware LVM/snapshot
What is Zpool/ZFS?
 ZFS is a file system designed by Sun Microsystems for the Solaris
  Operating System. Features include support for high storage capacities
  (16 exabytes per pool or 16 million terrabytes), snapshots and copy-on-
  write clones, continuous integrity checking (256bit CRC checks of
  every block) and automatic repair (scrubbing), RAID-Z and ACLs.
  (Found on Wiki)
 RAID 0 – 5: No protection against silent disk corruption and bit rot.
 Zpool: disk pool creation, iostatus, and health display (build RAIDZ,
  RAIDZ2, Jbods, stripes, mirrors, striped mirrors, etc…)
Open Solaris iscsitarget
 Uses industry standard iscsi target and initiator calls
 Extremely easy to use and seamlessly integrates with
 Allows for the creation of soft provisioned disks.
 ACL support, deny unwanted initiators.
 Iscsitadm list targets –v : details of each currently
  active targets
Replication Script; Mail; Cron
 Many available on the internet
 Modified a script from the web (author unknown) to
  work according to my requirements. Still in progress
  but works . (
 Use Cron to execute zfs-replicate on a schedule.
 Mail the results to your disk admins.
Vmware Enterprise
 Configure VMWare for iSCSI support
 Add targets to Vmware host adapters.
 Enable LVM snapshot support: GUI far more simpler
  than console.
Snapshots: How to?
 Reserve up to 40% of maximum pool capacity for snapshots, i.e.
  10TB pool, 6TB data, 4TB snapshots. Admin discretion and may
  be less depending on LUN configuration.
 Snapshots are the size of the used capacity of the LUN/partition.
 Making a snapshot is a breeze!
    /sbin/zfs snapshot pool/partition@snapshot
 Send the snapshot over to the remote site.
    /sbin/zfs send pool/partition@snapshot | ssh username@host \
     /sbin/zfs recv pool/partition
Replication types
 ZFS send/recv with SSH (avg. speed: 25MB/s at 256bit encryption)
    Slowest replication, doesn’t require dedicated network and secure.
    Different algorithms provide different data throughput.
    Stunnel may be quicker!
 ZFS send/recv with mbuffer (speeds: 80 to 120MB/s Avg: 360Gig/hr)
          lev@siscsi-sas:~$ zfs send sd/Linux@1 | mbuffer -b1024k -m 1500m -O ;LOCAL
          lev@piscsi-sas:~$ mbuffer -m 1500M -s1024k -I | zfs recv pdrive/Linux ;REMOTE
    Must have enough system memory (+4GB) to support large buffers.
    Non encrypted, requires network paths to be safe.
 ZFS send/recv with netcat/rsh (avg. speed: 35MB/s)
    Insecure data copy, just for comparison.
Data Recovery
 Activate offsite VM ESX Host.
 Access offsite disk storage LUNs.
    add iSCSI remote host to Virtual Center
 Re-add VM Disk (LUNs) to offsite VM Infrastructure.
    GUI: Advanced Features: LVM: EnableResignature
    CLI: /proc/vmware/config/LVM/EnableResignature
         Resignatured LUNs will appear automatically in the storage section of Virtual
 Re-add VM Guests from resignatured LUNs
 Offsite LUNs can be added to primary VM site for data recovery or

Tano Simonian
(ofc) 310 794 9669