Veritas Volume Manager 5.0 Troubleshooting Guide, HP-UX 11i v3, First Edition, May 2008

9Recovery from hardware failure

Understanding the plex state cycle

Changing plex states are part of normal operations, and do not necessarily

indicate abnormalities that must be corrected. A clear understanding of the

various plex states and their interrelationship is necessary if you want to be able

to perform the recovery procedures described in this chapter.

Figure 1-1 shows the main transitions that take place between plex states in

VxVM. (For more information about plex states, see the chapter “Creating and

Administering Plexes” in the Veritas Volume Manager Administrator’s Guide.)

Figure 1-1 Main plex state cycle

At system startup, volumes are started automatically and the vxvol start task

makes all CLEAN plexes ACTIVE. At shutdown, the

vxvol stop task marks all

ACTIVE plexes CLEAN. If all plexes are initially CLEAN at startup, this indicates

that a controlled shutdown occurred and optimizes the time taken to start up

the volumes.

Figure 1-2 shows additional transitions that are possible between plex states as

a result of hardware problems, abnormal system shutdown, and intervention by

the system administrator.

When first created, a plex has state EMPTY until the volume to which it is

attached is initialized. Its state is then set to CLEAN. Its plex kernel state

remains set to DISABLED and is not set to ENABLED until the volume is started.

PS: CLEAN

PKS: DISABLED

PS: ACTIVE

PKS: ENABLED

Start up

(vxvol start)

Shut down

(vxvol stop)

PS = plex state

PKS = plex kernel state