VERITAS Volume Manager 3.5 Administrator's Guide (September 2002)

Moving and Unrelocating Subdisks

240 VERITAS Volume Manager Administrator’s Guide

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 disk05 belonging to the volume home back to disk02,

enter the following command:

# vxassist -g rootdg move home !disk05 disk02

Here,!disk05 speciﬁes the current locationof thesubdisks, anddisk02 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 thedisk failure.vxunreloc allows youto move the hot-relocatedsubdisks

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 tothe originaloffsets.If you try tounrelocateto adisk that is smallerthan 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 backto thesame original offsets, aforce option

is available that allows you to move the subdisks to a speciﬁed disk without using the

original offsets. Refer to the vxunreloc(1M) manual page for more information.

The following examples demonstrate the use of vxunreloc.