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Creating and administering disk groups

Specifying a disk group to commands

Rules for determining the default disk group

It is recommended that you use the -goption to specify a disk group to VxVM commands that accept this option. If you do not specify the disk group, VxVM applies rules in the following order until it determines a disk group name:

Use the default disk group name that is specified by the environment variable VXVM_DEFAULTDG. This variable can also be set to one of the reserved system-wide disk group names: bootdg, defaultdg, or nodg. If the variable is undefined, the following rule is applied.

Use the disk group that has been assigned to the system-wide default disk group alias, defaultdg. See “Displaying and specifying the system-wide default disk group” on page 168. If this alias is undefined, the following rule is applied.

If the operation can be performed without requiring a disk group name (for example, an edit operation on disk access records), do so.

If none of these rules succeeds, the requested operation fails.

Caution: In releases of VxVM prior to 4.0, a subset of commands attempted to deduce the disk group by searching for the object name that was being operated upon by a command. This functionality is no longer supported. Scripts that rely on deducing the disk group from an object name may fail.

Displaying the system-wide boot disk group

To display the currently defined system-wide boot disk group, use the following command:

#vxdg bootdg

See the vxdg(1M) manual page for more information.

Displaying and specifying the system-wide default disk group

To display the currently defined system-wide default disk group, use the following command:

#vxdg defaultdg

If a default disk group has not been defined, nodg is displayed. Alternatively, you can use the following command to display the default disk group:

#vxprint -Gng defaultdg 2>/dev/null

In this case, if there is no default disk group, nothing is displayed.

Use the following command to specify the name of the disk group that is aliased by defaultdg:

# vxdctl defaultdg diskgroup

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HP Veritas Volume Manager 5.0 -UX 11i v3 manual Rules for determining the default disk group, # vxdg bootdg