Installation guide

36 Chapter 2:Hardware Installation and Operating System Configuration
point heartbeat connection on each cluster system (ecluster2 and ecluster3) as well as the IP alias
clusteralias used for remote cluster monitoring.
Verify correct formatting of the local host entry in the /etc/hosts file to ensure that it does not
include non-local systems in the entry for the local host. An example of an incorrect local host entry
that includes a non-local system (server1) is shown next:
127.0.0.1 localhost.localdomain localhost server1
A heartbeat channel may not operate properly if the format is not correct. For example, the channel
will erroneously appear to be offline. Check the /etc/hosts file and correct the file format by
removing non-local systems from the local host entry, if necessary.
Note that each network adapter must be configured with the appropriate IP address and netmask.
The following is an example of a portion of the output from the /sbin/ifconfig command on a
cluster system:
# ifconfig
eth0 Link encap:Ethernet HWaddr 00:00:BC:11:76:93
inet addr:192.186.1.81 Bcast:192.186.1.245 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:65508254 errors:225 dropped:0 overruns:2 frame:0
TX packets:40364135 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
Interrupt:19 Base address:0xfce0
eth1 Link encap:Ethernet HWaddr 00:00:BC:11:76:92
inet addr:10.0.0.1 Bcast:10.0.0.245 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
Interrupt:18 Base address:0xfcc0
The previous example shows two network interfaces on a cluster system: The eth0 network interface
for the cluster system and the eth1 (network interface for the point-to-point heartbeat connection).
2.3.3 Decreasing the Kernel Boot Timeout Limit
It is possible to reduce the boot time for a cluster system by decreasing the kernel boot timeout limit.
During the Linux boot sequence, the bootloader allows for specifying an alternate kernel to boot. The
default timeout limit for specifying a kernel is ten seconds.