6.15 Expanding /EXAVMIMAGES on the KVM host

Use this procedure to expand /EXAVMIMAGES using available space on the KVM host.

On Exadata database servers, local disk storage is governed by a volume manager, with all of the available storage space allocated to a single volume group. In turn, the volume group contains numerous logical volumes that support various file systems. On KVM hosts, most of the space is allocated to /EXAVMIMAGES, which is used for guest storage.

Typically, a modest amount of free space is preserved in the volume group so that a file system can be easily extended if required. Additional space is also available by adding the disk expansion kit to a database server. The kit consists of 4 hard drives, which are installed in the unused slots in the database server.

Note:

The disk expansion kit is supported on 2-socket Oracle Exadata Database Machine systems only.

If you installed the disk expansion kit, ensure that you have completed the procedure outlined in Adding the Disk Expansion Kit to Database Servers: X8M-2 and Prior before you proceed with this procedure:

  1. Examine the volume group to confirm the available free space.
    # vgs
       VG      #PV #LV #SN Attr   VSize VFree
       VGExaDb   1  11   0 wz--n- 3.27t <1.73t
  2. Confirm the current space allocation for /EXAVMIMAGES.
    # df /EXAVMIMAGES
    Filesystem                                1K-blocks      Used  Available Use% Mounted on 
    /dev/mapper/VGExaDb-LVDbExaVMImages      1572096000 250734224 1321361776  16% /EXAVMIMAGES
  3. Extend the logical volume associated with /EXAVMIMAGES.
    Use the lvextend command to add space to the logical volume.

    In the following example, all of the available free space is added to the logical volume.

    # lvextend -l +100%FREE /dev/VGExaDb/LVDbExaVMImages
       Size of logical volume VGExaDb/LVDbExaVMImages changed from 1.46 TiB (384000 extents) to 3.19 TiB (837430 extents).
       Logical volume VGExaDb/LVDbExaVMImages successfully resized.

    If you want to retain some free space for future use, then you can use a subset of the available free space. For example, the following command uses 90% of the available free space:

    # lvextend -l +90%FREE /dev/VGExaDb/LVDbExaVMImages

    Or, you can specify the amount of space that you want to add. For example, the following command expands the logical volume by 500 GB:

    # lvextend -L +500G /dev/VGExaDb/LVDbExaVMImages
  4. Extend the file system associated with /EXAVMIMAGES.
    Use the xfs_growfs command to extend the file system into the expanded logical volume.
    # xfs_growfs /EXAVMIMAGES 
    meta-data=/dev/mapper/VGExaDb-LVDbExaVMImages isize=512 agcount=32, agsize=12288000 blks
          =                       sectsz=512   attr=2, projid32bit=1
          =                       crc=1        finobt=0 spinodes=0 rmapbt=0
          =                       reflink=1    data
          =                       bsize=4096   blocks=393216000, imaxpct=5         
          =                       sunit=256    swidth=256 blks naming  
          =version 2              bsize=4096   ascii-ci=0 ftype=1 log     
          =internal               bsize=4096   blocks=192000, version=2
          =                       sectsz=512   sunit=8 blks, lazy-count=1 realtime
          =none                   extsz=4096   blocks=0, rtextents=0 data blocks changed from 393216000 to 857528320
  5. Confirm the expansion of /EXAVMIMAGES.
    # df /EXAVMIMAGES
    Filesystem                                1K-blocks      Used  Available Use% Mounted on 
    /dev/mapper/VGExaDb-LVDbExaVMImages      3429345280 261835784 3167509496   8% /EXAVMIMAGE