Modifying fixed block volume groups

This scenario describes how to modify fixed block storage within a storage unit.

To modify fixed block volume groups, you must have the command-line interface prompt, and you must be connected to a storage unit that will be used for open systems host system storage.
Adding volumes to a volume group and removing volumes from a volume group are typical storage management tasks. The volumes that are added to a volume group can be “unassigned” to a volume group, or they can be volumes that are assigned to a volume group but you want to move them to a different volume group. In either case, you are responsible for managing how the volumes are allocated to volume groups and how the volumes are reserved for future allocation. It is better that you maintain “unassigned” volumes in a volume group that is not accessible by any host system, thereby controlling the accessibility of volumes that are reserved for future allocation.

You can assign a fixed block volume to multiple volume groups. This might be necessary for some host system applications. However, damage to volume data can occur if a volume is accessed by different host systems using different file management systems. To assign a fixed block volume to multiple volume groups, perform the following steps:

  1. Find the fixed block volumes that are to be assigned to a volume group using the following command.

    dscli> lsfbvol -dev ID -datatype 512 | 520p | 520u -extpool ID

    The command creates a list of all volumes of the specified volume type within the specified extent pool. It includes only the volumes that are contained by the specified storage image.

  2. Retrieve the current volume group volume map using the following command.

    dscli> showvolgrp -dev ID volume_group_ID

    The command creates a list of volumes that are assigned to the target volume group.

  3. Modify the volume group using the following command.

    dscli> chvolgrp -dev ID -action add | remove | replace -volume ID,ID,...,ID volume_group_ID

    You can add or remove volume IDs to the list in order to add or remove volumes. This command applies the updated volume ID list.

Related reference
lsfbvol
chvolgrp
showvolgrp
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