Handling State Database Replica Errors
If a state database replica fails, the system continues to run if
at least half of the remaining replicas are available. The system panics when fewer
than half of the replicas are available.
The system can into reboot multiuser mode when at least one more
than half of the replicas are available. If fewer than a majority of
replicas are available, you must reboot into single-user mode and delete the unavailable replicas
(by using the metadb command).
For example, assume you have four replicas. The system continues to run as
long as two replicas (half the total number) are available. However, to reboot
the system, three replicas (half the total + 1) must be available.
In a two-disk configuration, you should always create at least two replicas on
each disk. For example, assume you have a configuration with two disks, and
you only create three replicas (two replicas on the first disk and
one replica on the second disk). If the disk with two replicas fails,
the system panics because the remaining disk only has one replica. This is
less than half the total number of replicas.
Note - If you create two replicas on each disk in a two-disk configuration, Solaris
Volume Manager still functions if one disk fails. But because you must have
one more than half of the total replicas available for the system to
reboot, you cannot reboot.
If a slice that contains a state database replica fails, the rest
of your configuration should remain in operation. Solaris Volume Manager finds a valid state
database during boot (as long as at least half +1 valid state
database replicas are available).
When you manually repair or enable state database replicas, Solaris Volume Manager
updates them with valid data.