6.2.12.6 chvolumegroup

Change attributes of a volume group.

Purpose

The chvolumegroup command allows you to modify the attributes of an Exascale volume group.

Syntax

chvolumegroup volume-group-ID 
              [ --attributes attribute=value[,attribute=value]... ]

Command Options

The options for the chvolumegroup command are:

  • volume-group-ID: Identifies the volume group being changed. You can use the lsvolumegroup command to find the identifier for each volume group.

  • --attributes: Optionally specifies attributes to change.

    The following attributes can be changed:

    • name: Specifies the name of the volume group.

    • resourceSharing: Optionally specifies how provisioned resources are shared by volumes in the group. Permitted values are:

      • aggregate: Configures the volume group to share the I/Os per second (IOPS) bandwidth provisioned to each volume in the group. In this case, a volume can exceed its provisioned limit by sharing unused IOPS provisioned to other volumes in the group.

        For example, consider a group with two volumes that are provisioned with 1000 IOPS each. In this example, aggregate resource sharing enables one volume to use 2000 IOPS when the other volume is idle.

      • specified: Configures the volume group to share the I/Os per second (IOPS) bandwidth limit specified by the iopsProvisioned attribute.

      • none: Specifies that the volume group is not a resource-sharing volume group. In this case, each volume is only subject to resource limits imposed at other levels, such as the individual volume level or the Exascale vault level.

    • iopsProvisioned: Optionally specifies the I/O bandwidth limit provisioned to the volume group, expressed in I/Os per second (IOPS).

    • owners: Modifies the volume group owners.

      A volume group can have up to two owners. To modify volume group ownership, you can add or remove one owner at a time.

      To add an owner, specify owners=+user-ID as an attribute setting. To remove an owner, use owners=-user-ID.

      For example, see Example 6-156.

Usage Notes

  • When resource sharing is disabled on a volume group (resourceSharing=none), the I/O bandwidth provisioned to the volume group must be zero (iopsProvisioned=0).

  • When a volume group uses aggregate resource sharing (resourceSharing=aggregate), the I/O bandwidth provisioned to the volume group must be zero (iopsProvisioned=0).

  • When a volume group employs specified resource sharing (resourceSharing=specified), the iopsProvisioned attribute value must be greater than zero.

  • A volume must always have at least one owner in common with each volume group it belongs to. Any modification violating this requirement is not permitted.

Examples

Example 6-156 Change the Volume Group Owners

The following examples show different ways to change the volume group owners.

  • The following command adds peter as an owner of the specified volume group: 

    @> chvolumegroup volgrp0001_08a99eb7e8ff41499dee41de75af3e62 --attributes owners=+peter

  • The following command removes dave as an owner of the specified volume group: 

    @> chvolumegroup volgrp0001_08a99eb7e8ff41499dee41de75af3e62 --attributes owners=-dave

Parent topic: Block Store Management