Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

91Administering disks
Changing the disk-naming scheme
You can either use enclosure-based naming for disks or the operating system’s naming
scheme (such as c#t#d#). Select menu item 20 from the
vxdiskadm main menu to
change the disk-naming scheme that you want VxVM to use. When prompted, enter y to
change the naming scheme. This restarts the
vxconfigd daemon to bring the new disk
naming scheme into effect.
Alternatively, you can change the naming scheme from the command line. The following
commands select enclosure-based and operating system-based naming respectively:
# vxddladm set namingscheme=ebn [persistence={yes|no}]
# vxddladm set namingscheme=osn [persistence={yes|no}]
The change is immediate whichever method you use. The optional persistence
argument allows you to select whether the names of disk devices that are displayed by
VxVM remain unchanged after disk hardware has been reconfigured and the system
rebooted. By default, both enclosure-based naming and operating system-based naming
are persistent.
The effect of enabling persistent device names in conjunction with operating system-based
naming is discussed in “Regenerating persistent device names” on page 91.
Regenerating persistent device names
The persistent device naming feature makes the names of disk devices persistent across
system reboots. If operating system-based naming is selected, each disk name is usually
set to the name of one of the paths to the disk. After hardware reconfiguration and a
subsequent reboot, the operating system may generate different names for the paths to the
disks. As DDL assigns persistent disk names using the persistent device name database
that was generated during a previous boot session, the disk names may no longer
correspond to the actual paths. This does not prevent the disks from being used, but the
association between the disk name and one of its paths is lost.
To find the relationship between a disk and its paths, run one of the following commands:
# vxdmpadm getsubpaths dmpnodename=disk_access_name
# vxdisk list disk_access_name
To update the disk names so that they correspond to the new path names
1 Remove the file that contains the existing persistent device name database:
# rm /etc/vx/disk.info
2 Restart the VxVM configuration demon:
# vxconfigd -k
This regenerates the persistent name database.