Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

On the importing host, import and rename the rootdg disk group with this

command:

# vxdg -tC -n newdg import diskgroup

The -t option indicates a temporary import name, and the -C option clears

import locks. The -n option specifies an alternate name for the rootdg being

imported so that it does not conflict with the existing rootdg. diskgroup is

the disk group ID of the disk group being imported (for example,

774226267.1025.tweety).

If a reboot or crash occurs at this point, the temporarily imported disk group

becomes unimported and requires a reimport.

After the necessary work has been done on the imported disk group, deport

it back to its original host with this command:

# vxdg -h hostname deport diskgroup

Here hostname is the name of the system whose rootdg is being returned

(the system name can be confirmed with the command uname -n).

This command removes the imported disk group from the importing host

and returns locks to its original host. The original host can then automatically

import its boot disk group at the next reboot.

Handling conflicting configuration copies

If an incomplete disk group is imported on several different systems, this can

create inconsistencies in the disk group configuration copies that you may need

to resolve manually. This section and following sections describe how such a

condition can occur, and how to correct it. (When the condition occurs in a cluster

that has been split, it is usually referred to as a serial split brain condition).

Example of a serial split brain condition in a cluster

This section presents an example of how a serial split brain condition might occur

for a shared disk group in a cluster. Conflicts between configuration copies can

also occur for private disk groups in clustered and non-clustered configurations

where the disk groups have been partially imported on different systems.

A campus cluster (also known as a stretch cluster or remote mirror configuration)

typically consists of a 2-node cluster where each component (server, switch and

storage) of the cluster exists in a separate building.

243Creating and administering disk groups

Handling conflicting configuration copies