VERITAS Volume Manager 3.1 Administrator's Guide

Recovery
Detecting and Replacing Failed Disks
Chapter 8 353
disk02 does not affect the hot-relocated subdisk disk01-01. However, a
replacement of disk01, followed by the unrelocate operation, moves
disk01-01 back to disk01 when the vxunreloc utility is run,
immediately after the replacement.
Restart vxunreloc After Errors
Internally, the vxunreloc utility moves the subdisks in three phases.The
first phase creates as many subdisks on the specified destination disk as
there are subdisks to be unrelocated. When the subdisks are created, the
vxunreloc utility fills in the comment field in the subdisk record with
the string UNRELOC as an identification. The second phase moves the
data. If all the subdisk moves are successful, the third phase cleans up
the comment field of the subdisk records.
Creating the subdisk is an all-or-none operation. If the vxunreloc utility
cannot create all the subdisks successfully, no subdisk is created and the
vxunreloc utility exits. The subdisk move operation is not all-or-none.
One subdisk move is independent of another, and as a result, if one
subdisk move fails, the vxunreloc utility prints an error message and
then exits. However, all of the subsequent subdisks remain on the disk
where they were hot-relocated and are not moved back. For subdisks that
were returned home, the comment field in their subdisk records is still
marked as UNRELOC because the cleanup phase is never executed.
If the system goes down after the new subdisks are made on the
destination, but before they are moved back, the unrelocate utility can
be executed again after thesystem comesback. As described above, when
a new subdisk is created, the vxunreloc utility sets the comment field of
the subdisk as UNRELOC. When the vxunreloc utility is re-executed, it
checks the offset, the len, and the comment fields of the subdisk on the
destination disk to determine if it was left on the disk at a previous
execution of the vxunreloc utility.
NOTE Do not manually modify the string UNRELOC in the comment field.
If one out of a series of subdisk moves fails, the vxunreloc utility exits.
Under this circumstance, you should check the error that caused the
subdisk move to fail and determine if the unrelocation can proceed.
When you re-execute the vxunreloc utility to resume the subdiskmoves,
it uses the subdisks created at a previous run.