After the setup of basic cluster hardware, proceed with installation
of Red Hat Enterprise Linux on each node and ensure that all systems recognize the
connected devices. Follow these steps:
Install Red Hat Enterprise Linux on all cluster nodes. Refer to
Red Hat Enterprise Linux Installation Guide for instructions.
In addition, when installing Red Hat Enterprise Linux, it is strongly
recommended to do the following:
Gather the IP addresses for the nodes and for the bonded
Ethernet ports, before installing Red Hat Enterprise Linux. Note that the IP
addresses for the bonded Ethernet ports can be private IP
addresses, (for example, 10.x.x.x).
Do not place local file systems (such as /,
/etc, /tmp, and
/var) on shared disks or on the same SCSI bus
as shared disks. This helps prevent the other cluster nodes from
accidentally mounting these file systems, and also reserves the
limited number of SCSI identification numbers on a bus for cluster
Place /tmp and /var on
different file systems. This may improve node performance.
When a node boots, be sure that the node detects
the disk devices in the same order in which they were detected
during the Red Hat Enterprise Linux installation. If the devices are not detected in
the same order, the node may not boot.
When using certain RAID storage configured with Logical Unit
Numbers (LUNs) greater than zero, it may be
necessary to enable LUN support by adding the following to
options scsi_mod max_scsi_luns=255
Reboot the nodes.
When using a terminal server, configure Red Hat Enterprise Linux to send
console messages to the console port.
Edit the /etc/hosts file on each cluster
node and include the IP addresses used in the cluster or ensure
that the addresses are in DNS. Refer to Section 2.4.1 Editing the /etc/hosts File for more information about
performing this task.
Ensure that no login (or getty) programs are
associated with the serial ports that are being used for the
remote power switch connection (if
applicable). To perform this task, edit the
/etc/inittab file and use a hash symbol
(#) to comment out the entries that correspond to
the serial ports used for the remote power
switch. Then, invoke the init q command.
Verify that all systems detect all the installed
The /etc/hosts file contains the IP
address-to-hostname translation table. The
/etc/hosts file on each node must contain entries
for IP addresses and associated hostnames for all cluster nodes.
As an alternative to the /etc/hosts file,
naming services such as DNS or NIS can be used to define the host
names used by a cluster. However, to limit the number of dependencies
and optimize availability, it is strongly recommended to use the
/etc/hosts file to define IP addresses for
cluster network interfaces.
The following is an example of an /etc/hosts
file on a node of a cluster that does not use DNS-assigned
The previous example shows the IP addresses and hostnames for
three nodes (node1,
node2, and node3),
Do not assign the node hostname to the localhost
(127.0.0.1) address, as this causes issues with the CMAN cluster management
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
An Ethernet connection may not operate properly if the format of
the /etc/hosts file is not correct. 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 example shows a portion of the output from the
/sbin/ip addr list command on a cluster node:
2: eth0: <BROADCAST,MULTICAST,UP> mtu 1356 qdisc pfifo_fast qlen 1000
link/ether 00:05:5d:9a:d8:91 brd ff:ff:ff:ff:ff:ff
inet 10.11.4.31/22 brd 10.11.7.255 scope global eth0
inet6 fe80::205:5dff:fe9a:d891/64 scope link
valid_lft forever preferred_lft forever
You may also add the IP addresses for the cluster nodes to your
DNS server. Refer to the Red Hat Enterprise Linux System Administration Guide for
information on configuring DNS, or consult your network administrator.
It is possible to reduce the boot time for a node by
decreasing the kernel boot timeout limit. During the Red Hat Enterprise Linux boot
sequence, the boot loader allows for specifying an alternate kernel to
boot. The default timeout limit for specifying a kernel is ten
To modify the kernel boot timeout limit for a node, edit the
appropriate files as follows:
When using the GRUB boot loader, the timeout parameter in
/boot/grub/grub.conf should be modified to
specify the appropriate number of seconds for the
timeout parameter. To set this interval to 3
seconds, edit the parameter to the following:
timeout = 3
When using the LILO or ELILO boot loaders, edit the
/etc/lilo.conf file (on x86 systems) or the
elilo.conf file (on Itanium systems) and specify
the desired value (in tenths of a second) for the
timeout parameter. The following example sets
the timeout limit to three seconds:
timeout = 30
To apply any changes made to the
/etc/lilo.conf file, invoke the
On an Itanium system, to apply any changes made to the
/boot/efi/efi/redhat/elilo.conf file, invoke the