Changing or displaying the characteristics of a volume group

You can change or display the characteristics of a volume group.

To change or display a shared volume group:
  1. From the command line, enter smit cl_admin.
  2. In SMIT, select Storage > Volume Groups > Set Characteristics of a Volume Group > Change/Show characteristics of a Volume Group and press Enter.
  3. Select Volume group. SMIT displays the Change/Show characteristics of a Volume Group panel.
  4. Complete the selections as follows and press Enter
    Table 1. Change or show a volume group fields
    Field Value
    Volume group name The volume group selected from the prior pick list of volume groups known across the cluster
    Resource Group Name The resource group (if any) that owns the selected volume group.
    Node Names The list of nodes on which the volume group is known.
    Activate volume group automatically at system restart? Specifies whether the volume group is automatically activated during the system startup. If a volume group is infrequently used, do not active the volume group at system startup because it uses kernel resources (memory).
    A QUORUM of disks required to keep the volume group on-line ? Determines whether the volume group is automatically varied off after losing its quorum of physical volumes. The default value is yes, which means that the volume group is automatically varied off after losing its quorum of physical volumes (51% of descriptor areas). The value no indicates that the volume group stays active until it looses all of its physical volumes.
    Enable Fast Disk Takeover or Concurrent Access Change the volume group to Enhanced Concurrent Mode. Enhanced concurrent mode can be used for fast disk takeover, or it can be used in a resource group that is online on all available nodes (OAAN).
    Change to big VG format? Changes the volume group to Big VG format. This can accommodate up to 128 physical volumes and 512 logical volumes. For more information about the Big VG format, see the mkvg command.
    Change to scalable VG format? Changes the volume group to Scalable VG format. This format can accommodate up to 1024 physical volumes and 4096 logical volumes. For more information about the Scalable VG format, see the mkvg command.
    LTG Size in kbytes Sets the group size of the logical track, in number of kilobytes, for the volume group. The specified value must be 128, 256, 512, or 1024. The number that you specify must be less than or equal to the maximum transfer size of all disks in the volume group. The default size is 128 kilobytes.
    Set hotspare characteristics Sets the sparing characteristics for the volume group specified by the Volume Group parameter. Either allows or prohibits the automatic migration of failed disks. For more information about hotspare characteristics, see the mkvg command.
    Max PPs per VG in units of 1024 Increases the number of physical partitions a volume group can accommodate. The Physical Partitions variable is represented in units of 1024 partitions. Valid values are 64, 128, 256, 512, 768, 1024, and 2048. The value must be greater than the current value or no action is taken. This option is only valid with Scalable-type volume groups.
    Max Logical Volumes Increases the number of logical volumes that can be created. Valid values are 512, 1024, 2048, and 4096. The value must be greater than the current value, otherwise no action is taken. This option is valid only with scalable-type volume groups.
    Mirror Pool Strictness Enables mirror pool strictness for the volume group.
    Note:
    • If you specify yes, mirror pools must be used on each logical volume in the volume group.
    • If you specify superstrict, super-strict mirror pools are enforced on the selected volume group.
    LVM Preferred Read LVM preferred read options follows:
    • Roundrobin - Default policy for LVM Preferrred read copy. LVM determines which mirror copy to read.
    • Favour copy - Select this option if you want to read from the Flash storage irrespective of the resource group location.
    • Site Affinity - Select this option if you want to read from the local storage path that is based on the resource group location.
    Enable LVM Encryption Use this option to enable or disable the Logical Volume Manager (LVM) encryption. LVM encryption is not supported on legacy volume groups.
  5. The C-SPOC utility verifies communication paths and version compatibility, and then executes the command on all nodes that you selected. If cross-site LVM mirroring is enabled, the associated configuration is verified.