392Administering hot-relocation

Moving and unrelocating subdisks

subdisks using vxassist” on page 392 and “Moving and unrelocating subdisks using vxunreloc” on page 392.

Moving and unrelocating subdisks using vxassist

You can use the vxassist command to move and unrelocate subdisks. For example, to move the relocated subdisks on mydg05 belonging to the volume home back to mydg02, enter the following command:

#vxassist -g mydg move home !mydg05 mydg02

Here, !mydg05 specifies the current location of the subdisks, and mydg02 specifies where the subdisks should be relocated.

If the volume is enabled, subdisks within detached or disabled plexes, and detached log or RAID-5 subdisks, are moved without recovery of data.

If the volume is not enabled, subdisks within STALE or OFFLINE plexes, and stale log or RAID-5 subdisks, are moved without recovery. If there are other subdisks within a non-enabled volume that require moving, the relocation fails.

For enabled subdisks in enabled plexes within an enabled volume, data is moved to the new location, without loss of either availability or redundancy of the volume.

Moving and unrelocating subdisks using vxunreloc

VxVM hot-relocation allows the system to automatically react to I/O failures on a redundant VxVM object at the subdisk level and then take necessary action to make the object available again. This mechanism detects I/O failures in a subdisk, relocates the subdisk, and recovers the plex associated with the subdisk. After the disk has been replaced, vxunreloc allows you to restore the system back to the configuration that existed before the disk failure. vxunreloc allows you to move the hot-relocated subdisks back onto a disk that was replaced due to a failure.

When vxunreloc is invoked, you must specify the disk media name where the hot-relocated subdisks originally resided. When vxunreloc moves the subdisks, it moves them to the original offsets. If you try to unrelocate to a disk that is smaller than the original disk that failed,vxunreloc does nothing except return an error.

vxunreloc provides an option to move the subdisks to a different disk from where they were originally relocated. It also provides an option to unrelocate subdisks to a different offset as long as the destination disk is large enough to accommodate all the subdisks.

If vxunreloc cannot replace the subdisks back to the same original offsets, a force option is available that allows you to move the subdisks to a specified disk