Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

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.
Administering CVM from the slave node
CVM requires that the master node of the cluster executes configuration
commands, which change the object configuration of a CVM shared disk group.
Examples of configuration changes include creating shared disk groups, importing
shared disk groups, deporting shared disk groups, and creating volumes or
snapshots in a shared disk group.
Starting in this release, you can issue most configuration commands that operate
on the shared disk group from any node in the cluster. If you issue the command
on the slave node, CVM ships the commands from the slave node to the master
node. CVM then executes the command on the master node. In normal conditions,
we recommend that you issue configuration-changing commands for a shared
disk group on the master node. If the circumstances require, you can issue these
commands from the slave node.
Commands that operate on private disk groups are not shipped to the master
node. Similarly, CVM does not ship commands that operate locally on the slave
node, such as vxprint and vxdisk list.
When you issue a command on the slave that is executed on the master, the
command output (on the slave node) displays the object names corresponding to
the master node. For example, the command displays the disk access name (daname)
from the master node.
When run from a slave node, a query command such as vxtask or vxstat displays
the status of the commands on the slave node. The command does not show the
status of commands that originated from the slave node and that are executing
on the master node.
Note the following error handling for commands that you originate from the slave
node, which CVM executes on the master:
■ If the vxconfigd daemon on either the slave node or on the master node fails,
the command exits. The instance of the command on the master also exits. To
determine if the command executed successfully, use the vxprint command
to check the status of the VxVM objects.
■ If the slave node that shipped the command or the master node leaves the
cluster while the master is executing the command, the command exits on the
master node as well as on the slave node. To determine if the command
executed successfully, use thevxprint command to check the status of the
VxVM objects.
Administering cluster functionality (CVM)
Administering VxVM in cluster environments
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