VERITAS Volume Manager 3.5 Administrator's Guide (September 2002)

Chapter 10, Administering Cluster Functionality

Administering VxVM in Cluster Environments

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Recovering Volumes in Shared Disk Groups

Note Volumes can only be recovered on the master node.

The vxrecover utility is used to recover plexes and volumes after disk replacement.

When a node leaves a cluster, it can leave some mirrors in an inconsistent state. The

vxrecover utility can be used to recover such volumes. The -c option to vxrecover

causes it to recover all volumes in shared disk groups. The vxconfigd daemon

automatically calls the vxrecover utility with the -c option when necessary.

Note While the vxrecover utility is active, there can be some degradation in system

performance.

Obtaining Cluster Performance Statistics

The vxstat utility returns statistics for speciﬁed objects. In a cluster environment,

vxstat gathers statistics from all of the nodes in the cluster. The statistics give the total

usage, by all nodes, for the requested objects. If a local object is speciﬁed, its local usage is

returned.

You can optionally specify a subset of nodes using the following form of the command:

# vxstat -g diskgroup -n node[,node...]

wherenodeis an integer. Ifacomma-separated listof nodesissupplied, the vxstat utility

displays the sum of the statistics for the nodes in the list.

For example, to obtain statistics for node 2, volume vol1,use the following command:

# vxstat -g group1 -n 2 vol1

This command produces output similar to the following:

OPERATIONS BLOCKS AVG TIME(ms)

TYP NAME READ WRITE READ WRITE READ WRITE

vol vol1 2421 0 600000 0 99.0 0.0

To obtain and display statistics for the entire cluster, use the following command:

# vxstat -b

The statistics for all nodes are summed. For example, if node 1 performed 100 I/O

operations and node 2 performed 200 I/O operations, vxstat -b displays a total of 300

I/O operations.