Figure 4-1 pdsh Architecture

For more information on pdsh and dshbak, refer to their reference manpages.

4.2 pdsh Utility Wrappers

Administrators can build wrapper commands around pdsh for commands that are frequently used across multiple systems and Serviceguard clusters. Several such wrapper commands are provided with DSAU. These wrappers are Serviceguard cluster-aware and default to fanning out cluster-wide when used in a Serviceguard environment. These wrappers support most standard pdsh command line options and also support long options (--optionsyntax) .

cexec

cexec is a general purpose pdsh wrapper. In addition to the standard pdsh features,

 

cexec includes a reporting feature. Use the --report_locoption to have cexec

 

display the report location for a command. The command report records the

 

command issued in addition to the nodes where the command succeeded, failed,

 

or the nodes that were unreachable. The report can be used with the --retryoption

 

to replay the command against nodes that failed, succeeded, were unreachable, or

 

all nodes.

ccp

ccp is a wrapper for pdcp and copies files cluster-wide or to the specified set of

 

systems.

cps

cps fans out a ps command across a set of systems or cluster.

ckill

ckill allows the administrator to signal a process by name since the pid of a specific

 

process will vary across a set of systems or the members of a cluster.

cuptime

cuptime displays the uptime statistics for a set of systems or a cluster.

cwall

cwall displays a wall(1M) broadcast message on multiple hosts.

All the wrappers support the CFANOUT_HOSTS environment variable when not executing in a Serviceguard cluster. The environment variable specifies a file containing the list of hosts to target, one hostname per line. This will be used if no other host specifications are present on the command line. When no target nodelist command line options are used and CFANOUT_HOSTS is undefined, the command will be executed on the local host.

For more information on these commands, refer to their reference manpages.

84 Command Fanout