Create physical volumes that LVM can use

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Create physical volumes that LVM can use Powered By Docstoc
  The basic steps to take to begin using LVM are as follows:

      +   Identify the disks to be used for LVM.

      +    Create an LVM data structure on each identified disk (see

      +    Collect all the physical volumes to form a new volume group
          (see vgcreate(1M)).

      +    Create logical volumes from the space in the volume group
          (see lvcreate(1M)).

      +    Use each logical volume as if it were a disk section (create
          a file system, or use for raw access).

   To configure disk /dev/dsk/c0t0d0 as part of a new volume group named

      First, initialize the disk for LVM with the pvcreate command.

          pvcreate /dev/rdsk/c0t0d0

      Then, create the pseudo device file that is used by the LVM

          mkdir /dev/vg01
          mknod /dev/vg01/group c 64 0x030000

      The minor number for the group file should be unique among all
      the volume groups on the system. It has the format 0xNN0000,
      where NN ranges from 00 to 09. The maximum value of NN is
      controlled by the kernel tunable parameter, maxvgs.

      Create the volume group, vg01, containing the physical volume,
      /dev/dsk/c0t0d0, with the vgcreate command.

          vgcreate /dev/vg01 /dev/dsk/c0t0d0

      You can view information about the newly created volume group
      with the vgdisplay command.

          vgdisplay -v /dev/vg01

      Create a logical volume of size 100 MB, named usrvol, on this
      volume group with the lvcreate command.

          lvcreate -L 100 -n usrvol /dev/vg01

      This creates two device files for the logical volume,
      /dev/vg01/usrvol, which is the block device file, and
      /dev/vg01/rusrvol, which is the character (raw) device file.

      You can view information about the newly created logical volume
         with the lvdisplay command.

             lvdisplay /dev/vg01/lvol1

         Any operation allowed on a disk partition is allowed on the
         logical volume. Thus, you can use usrvol to hold a file system.

             newfs /dev/vg01/rusrvol
             mount /dev/vg01/usrvol /usr

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1. create device special files
         insf -e

2. Create physical volumes that LVM can use

check if the disk is already in lvm
strings /etc/lvmtab | grep '/dev/dsk' | grep dskname
Ex:strings /etc/lvmtab |grep "/dev/dsk" |grep c1t2d3

check disktype:
Ex: diskinfo /dev/rdsk/c1t2d0
    SCSI describe of /dev/rdsk/c1t2d0:
            vendor: EMC
          product id: SYMMETRIX
              type: direct access
              size: 8838720 Kbytes
      bytes per sector: 512

Create physical volume that LVM can use:
        pvcreate [-f] characterdisk
        Ex: pvcreate -f /dec/rdsk/c1t2d0

3. Create volume group
        check the existing volume group
        Ex: strings /etc/lvmtab |grep vg

          mkdir /dev/vg02
          cd /dev/vg02
          mknod group c 64 0x${vgnum}0000
          Ex:mknod group c 64 0x0230000

          vgcreate -p 30 vgname disks
          vgcreate -p 30 /dev/vg02 /dev/dsk/c1t2d0 /dev/dsk/c1t3d0

4. Delete voulme group
        remove disk from volume group
        vgreduce volumegroup disk
        Ex: vgreduce /dev/vg02 /dev/dsk/c1t2d0

          remove volume group
          Ex: vgremove /dev/vg02
               rm -r /dev/vg02

Create File System On HP

1. check free space: vgdisplay
        vgdisplay volumegroup
        Ex: vgdisplay vg01

2. Create logical volume: lvcreate
        lvcreate -L sizeinMB -n filesystemname volumegroupname
        Ex: lvcreate -L 3500 -n u01 /dev/vg01

3. Create file system: newfs
        newfs -F filetype -o options rawdevicename
        Ex: newfs -F vxfs -o largefiles /dev/vg01/ru01

4. Create dir: mkdir
        mkdir mountpoint
        Ex: mkdir /u01

5. Add file system to /etc/fstab: vi
         logicalvolume directory filesystem options
         Ex: /dev/vg01/u01 /u01 vxfs largefiles,delaylog 0 2

6. Change owner of mount point: chown
       chown -R owner:group dir
       Ex: chown -R oracle:install /u01

Extend file system on HP
1. Stop all processes using logical volumes: fuser
         fuser logicalvolumes
         Ex: fuser /u01
   or get into single user mode

2. Extend logical volume: lvextend
        lvextend -L newtotalsizeinMB LogicalVolume
        Ex: lvextend -L 5000 /dev/vg01/u01

3. Umount the file system: umount
       umount filesystem
       Ex: umount /u01

4. Extend the file system: extendfs
        extendfs rawdevice
        Ex: extendfs /dev/vg01/ru01

5. Mount the file system: mount
       mount filesystem
       Ex: mount /u01

Remove filesystem on HP
1. umount file system: umount
       umount filesystem
          Ex: umount /u02

2. Remove logical volumn: lvremove
       lvremove -f logicalvolname
       Ex: lvremove -f /dev/vg01/u02

3. Remove mount point: rmdir
       rmdir mountpoint
       Ex: rmdir /u02



          lvcreate -L $needed -n moreswap -C y /dev/$vgname
          echo /dev/$vgname/moreswap / swap defaults 0 0 >>/etc/fstab
          swapon -a

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