Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

■ AIX coexistence label
■ HP-UX coexistence or VxVM ID block
There are also backup copies of each. If any of the primary labels become corrupted,
VxVM will not bring the disk online and user intervention is required.
If two labels are intact, the disk is still recognized as a cdsdisk (though in the
error state) and vxdisk flush can be used to restore the CDS disk labels from
their backup copies.
Note: For disks larger than 1 TB, cdsdisks use the EFI layout. The procedure to
restore disk labels does not apply to cdsdisks with EFI layout.
Primary labels are at sectors 0, 7, and 16; and a normal flush will not flush sectors
7 and 16. Also, the private area is not updated as the disk is not in a disk group.
There is no means of finding a “good” private region to flush from. In this case,
it is possible to restore the CDS disk labels from the existing backups on disk using
the flush operation.
If a corruption happened after the labels were read and the disk is still online and
part of a disk group, then a flush operation will also flush the private region.
Warning: Caution and knowledge must be employed because the damage could
involve more than the CDS disk labels. If the damage is constrained to the first
128K, the disk flush would fix it. This could happen if another system on the fabric
wrote a disk label to a disk that was actually a CDS disk in some disk group.
To rewrite the CDS ID information on a specific disk
■ Type the following command:
# vxdisk flush disk_access_name
This rewrites all labels except sectors 7 and 16.
To rewrite all the disks in a CDS disk group
■ Type the following command:
# vxdg flush diskgroup
This rewrites all labels except sectors 7 and 16.
To forcibly rewrite the AIX coexistence label in sector 7 and the HP-UX coexistence
label or VxVM ID block in sector 16
■ Type the following command:
Migrating data between platforms
Maintaining your system
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