Managing Serviceguard Seventeenth Edition, First Reprint December 2009
NOTE: If a NIC fails, the affected node will be able to fail over to a standby LAN so
long as the node is running in the cluster. But if a NIC that is used by Serviceguard
fails when the affected node is not running in the cluster, Serviceguard will not be able
to restart the node. (For instructions on replacing a failed NIC, see “Replacing LAN or
Fibre Channel Cards” (page 372).)
1. Edit the /etc/hosts file on all nodes in the cluster. Add name resolution for all
heartbeat IP addresses, and other IP addresses from all the cluster nodes; see
“Configuring Name Resolution” (page 199) for discussion and examples.
NOTE: For each cluster node, the public-network IP address must be the first
address listed. This enables other applications to talk to other nodes on public
networks.
2. If you are using DNS, make sure your name servers are configured in
/etc/resolv.conf, for example:
domain cup.hp.com
search cup.hp.com hp.com
nameserver 15.243.128.51
nameserver 15.243.160.51
3. Edit or create the /etc/nsswitch.conf file on all nodes and add the following
text, if it does not already exist:
• for DNS, enter (two lines):
hosts: files [NOTFOUND=continue UNAVAIL=continue] dns [NOTFOUND=return UNAVAIL=return]
ipnodes: files [NOTFOUND=continue UNAVAIL=continue] dns [NOTFOUND=return
UNAVAIL=return]
• for NIS, enter (two lines):
hosts: files [NOTFOUND=continue UNAVAIL=continue] nis [NOTFOUND=return UNAVAIL=return]
ipnodes: files [NOTFOUND=continue UNAVAIL=continue] nis [NOTFOUND=return
UNAVAIL=return]
If a line beginning with the string hosts: or ipnodes: already exists, then make
sure that the text immediately to the right of this string is (on one line):
files [NOTFOUND=continue UNAVAIL=continue] dns [NOTFOUND=return UNAVAIL=return]
or
files [NOTFOUND=continue UNAVAIL=continue] nis [NOTFOUND=return UNAVAIL=return]
This step is critical, allowing the cluster nodes to resolve hostnames to IP addresses
while DNS, NIS, or the primary LAN is down.
4. Create a $SGCONF/cmclnodelist file on all nodes that you intend to configure
into the cluster, and allow access by all cluster nodes. See “Allowing Root Access
to an Unconfigured Node” (page 197).
Preparing Your Systems 201