VERITAS Volume Manager 3.1 Administrator's Guide

Cluster Functionality

Cluster Functionality Overview

Chapter 7 305

• If any volume in a shared disk group is open, the VxVM shutdown

procedure returns failure. The shutdown procedure can be retried

repeatedly until it succeeds. There is no timeout checking in this

operation—it is intended as a service that veriﬁes that the clustered

applications are no longer active.

NOTE Once shutdown succeeds, the node has left the cluster. It is not possible

to access the shared volumes until the node joins the cluster again.

Since shutdown can be a lengthy process, other reconﬁgurations can take

place while shutdown is in progress. Normally, the shutdown attempt is

suspended until the other reconﬁguration completes. However, if it is

already too far advanced, the shutdown may complete ﬁrst.

Node Abort

If a node does not leave cleanly, this is because the host crashed. After a

node abort or crash, the shared volumes must be recovered (either by a

surviving node or by a subsequent cluster restart) because it is very

likely that there are unsynchronized mirrors.

Cluster Shutdown

When all the nodes in the cluster leave, the determination of whether or

not the shared volumes should be recovered has to be made at the next

cluster startup. If all nodes left cleanly, there is no need for recovery. If

the last node left cleanly and resynchronization resulting from the

non-clean leave of earlier nodes was complete, there is also no need for

recovery. However, recovery must be performed if the last node did not

leave cleanly or if resynchronization from previous leaves was not

complete.