VERITAS Volume Manager 4.1 Administrator's Guide

Administering Hot-Relocation
Moving and Unrelocating Subdisks
Chapter 9 347
The destination disk should have at least as much storage capacity as
was in use on the original disk. If there is not enough space, the
unrelocate operation will fail and none of the subdisks will be moved.
Forcing hot-relocated subdisks to accept different offsets
By default, vxunreloc attempts to move hot-relocated subdisks to their
original offsets. However, vxunreloc fails if any subdisks already occupy
part or all of the area on the destination disk. In such a case, you have
two choices:
• Move the existing subdisks somewhere else, and then re-run
vxunreloc.
• Use the -f option provided by vxunreloc to move the subdisks to the
destination disk, but leave it to vxunreloc to find the space on the
disk. As long as the destination disk is large enough so that the
region of the disk for storing subdisks can accommodate all subdisks,
all the hot-relocated subdisks will be “unrelocated” without using the
original offsets.
Assume that disk01 failed and the subdisks were relocated and that you
want to move the hot-relocated subdisks to disk05 where some subdisks
already reside. You can use the force option to move the hot-relocated
subdisks to disk05, but not to the exact offsets:
# vxunreloc -g newdg -f -n disk05 disk01
Examining which subdisks were hot-relocated from a disk
If a subdisk was hot relocated more than once due to multiple disk
failures, it can still be unrelocated back to its original location. For
instance, if disk01 failed and a subdisk named disk01-01 was moved to
disk02, and then disk02 experienced disk failure, all of the subdisks
residing on it, including the one which was hot-relocated to it, will be
moved again. When disk02 was replaced, a vxunreloc operation for
disk02 will do nothing to the hot-relocated subdisk disk01-01. However,
a replacement of disk01 followed by a vxunreloc operation, moves
disk01-01 back to disk01 if vxunreloc is run immediately after the
replacement.
After the disk that experienced the failure is fixed or replaced,
vxunreloc can be used to move all the hot-relocated subdisks back to the
disk. When a subdisk is hot-relocated, its original disk-media name and
the offset into the disk, are saved in the configuration database. When a