Managing Serviceguard A.11.20, March 2013

on whether all nodes are currently down (that is, no cluster daemons are running), or whether you
are starting the cluster daemon on an individual node.
Note the distinction that is made in this chapter between adding an already configured node to
the cluster and adding a new node to the cluster configuration. An already configured node is one
that is already entered in the cluster configuration file; a new node is added to the cluster by
modifying the cluster configuration file.
NOTE: Manually starting or halting the cluster or individual nodes does not require access to the
Quorum Server, if one is configured. The Quorum Server is only used when tie-breaking is needed
following a cluster partition.
Starting the Cluster When all Nodes are Down
You can use Serviceguard Manager, or Serviceguard commands as shown below, to start the
cluster.
Using Serviceguard Commands to Start the Cluster
Use the cmruncl command to start the cluster when all cluster nodes are down. Particular command
options can be used to start the cluster under specific circumstances.
The following command starts all nodes configured in the cluster and verifies the network information:
cmruncl
By default, cmruncl will do network validation, making sure the actual network setup matches
the configured network setup. This is the recommended method. If you have recently checked the
network and find the check takes a very long time, you can use the -w none option to bypass the
validation.
Use the -v (verbose) option to display the greatest number of messages.
The -n option specifies a particular group of nodes. Without this option, all nodes will be started.
The following example starts up the locally configured cluster only on ftsys9 and ftsys10. (This
form of the command should only be used when you are sure that the cluster is not already running
on any node.)
cmruncl -v -n ftsys9 -n ftsys10
CAUTION: Serviceguard cannot guarantee data integrity if you try to start a cluster with the
cmruncl -n command while a subset of the cluster's nodes are already running a cluster. If the
network connection is down between nodes, using cmruncl -n might result in a second cluster
forming, and this second cluster might start up the same applications that are already running on
the other cluster. The result could be two applications overwriting each other's data on the disks.
Adding Previously Configured Nodes to a Running Cluster
You can use Serviceguard Manager, or Serviceguard commands as shown below, to bring a
configured node up within a running cluster.
Using Serviceguard Commands to Add Previously Configured Nodes to a Running Cluster
Use the cmrunnode command to join one or more nodes to an already running cluster. Any node
you add must already be a part of the cluster configuration. The following example adds node
ftsys8 to the cluster that was just started with only nodes ftsys9 and ftsys10. The-v (verbose)
option prints out all the messages:
cmrunnode -v ftsys8
By default, cmrunnode will do network validation, making sure the actual network setup matches
the configured network setup. This is the recommended method. If you have recently checked the
282 Cluster and Package Maintenance