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

163Creating and administering disk groups
Adding a disk to a disk group
You can use the cds attribute with the vxdg init command to specify whether a new
disk group is compatible with the Cross-platform Data Sharing (CDS) feature. In Veritas
Volume Manager 4.0 and later releases, newly created disk groups are compatible with
CDS by default (equivalent to specifying cds=on). If you want to change this behavior,
edit the file /etc/default/vxdg, and set the attribute-value pair cds=off in this
file before creating a new disk group.
Alternatively, you can use the following command to set this attribute for a disk group:
# vxdg -g diskgroup set cds=on|off
Adding a disk to a disk group
To add a disk to an existing disk group, use menu item 1 (Add or initialize one
or more disks) of the vxdiskadm command. For details of this procedure, see
“Adding a disk to VxVM” on page 97.
You can also use the vxdiskadd command to add a disk to a disk group, for example:
# vxdiskadd c1t1d0
where c1t1d0 is the device name of a disk that is not currently assigned to a disk group.
The command dialog is similar to that described for the vxdiskadm command in
“Adding a disk to VxVM” on page 97.
Removing a disk from a disk group
Note: Before you can remove the last disk from a disk group, you must disable the disk
group as described in “Disabling a disk group” on page 197. Alternatively, you can
destroy the disk group as described in “Destroying a disk group” on page 197.
A disk that contains no subdisks can be removed from its disk group with this command:
# vxdg [-g diskgroup] rmdisk diskname
For example, to remove mydg02 from the disk group, mydg, use this command:
# vxdg -g mydg rmdisk mydg02
If the disk has subdisks on it when you try to remove it, the following error message is
displayed:
VxVM vxdg ERROR V-5-1-552 Disk diskname is used by one or more
subdisks
Use -k to remove device assignment.
Using the -k option allows you to remove the disk even if subdisks are present. For more
information, see the vxdg(1M) manual page.
Caution: Use of the -k option to vxdg can result in data loss.