Managing Serviceguard A.11.20, March 2013

2. If the cluster does not yet exist, set up root access among the prospective nodes:
a. If you have not already done so, set up ssh public/private key pairs on each node. This
will allow the necessary commands to operate on all the prospective nodes before a
cluster is formed.
The simplest way to do this is via the DSAU csshsetup command; for example, if you
are setting up a two-node cluster with nodes node1 and node2, and you are logged in
on node1:
csshsetup -r node2
For a large number of nodes, you might want to enter the node names into a file and use
the -f option to get csshsetup to read the names from the file; for example, if you
have stored the names in the file /etc/cmcluster/sshhosts:
csshsetup -r -f /etc/cmcluster/sshhosts
For more information about setting up ssh keys, see the HP-UX Secure Shell Getting
Started Guide at http://www.hp.com/go/hpux-core-docs.
b. Configure root access to each prospective node, using the hostname portion (only) of the
fully-qualified domain name:
cmpreparecl -n <node_name> -n <node_name> ...
For example, for a cluster that will consist four nodes, node1, node2, node3, and
node4:
cmpreparecl -n node1 -n node2 -n node3 -n node4
NOTE: Serviceguard must be installed on all of the nodes listed, and you must be logged
in as superuser on one of these nodes to run the command.
3. Create the cDSFs.
NOTE: cDSFs apply only to shared storage; they will not be generated for local storage,
such as root, boot, and swap devices.
• If the cluster does not exist yet, specify the name of each prospective node, for example:
cmsetdsfgroup -n node1 -n node2 -n node3 -n node4
• If the cluster does exist, you can simply run:
cmsetdsfgroup -c
NOTE: You must be logged in as superuser on one of the cluster nodes. You do not
need to provide the cluster name.
The cDSFs created by cmsetdsfgroup reside in /dev/cdisk for block device files and /dev/
rcdisk for character devicefiles. You should use these new device files exclusively when you
configure the cluster lock (if any) and package storage; see “Specifying a Lock Disk” (page 193),
“Specifying a Lock LUN” (page 194), and “Creating the Storage Infrastructure and file systems with
LVM, VxVM and CVM” (page 181).
Adding a Node to a cDSF Group
When you add a new node to a cluster that uses cDSFs, you also need to add the node to the
cDSF group. For example, to add the new cluster node node5 to the existing cDSF group, run the
following command from one of the existing members of the group:
cmsetdsfgroup –a –n node5
Preparing Your Systems 165