When a host in a non-clustered environment imports a disk group, an import lock is written on all disks in that disk group. The import lock is cleared when the host deports the disk group. The presence of the import lock prevents other hosts from importing the disk group until the importing host has deported the disk group.
Specifically, when a host imports a disk group, the import normally fails if any disks within the disk group appear to be locked by another host. This allows automatic re-importing of disk groups after a reboot (autoimporting) and prevents imports by another host, even while the first host is shut down. If the importing host is shut down without deporting the disk group, the disk group can only be imported by another host by clearing the host ID lock first (discussed later).
The import lock contains a host ID (in Veritas Volume Manager, this is the host name) reference to identify the importing host and enforce the lock. Problems can therefore arise if two hosts have the same host ID.
Since Veritas Volume Manager uses the host name as the host ID (by default), it is advisable to change the host name of one machine if another machine shares its host name. To change the host name, use the
hostid new_hostname command.