Installation guide

Note

When using SELinux with Red Hat Cluster Suite in a VM environment, you should ensure that

the SELinux boolean fenced_can_network_connect is persistently set to on. This allows

the fence_xvm fencing agent to work properly, enabling the system to fence virtual machines.

For more information about SELinux, refer to Deployment Guide for Red Hat Enterprise Linux 5.

2.9. Mult icast Addresses

Red Hat Cluster nodes communicate among each other using multicast addresses. Therefore, each

network switch and associated networking equipment in a Red Hat Cluster must be configured to

enable multicast addresses and support IGMP (Internet Group Management Protocol). Ensure that

each network switch and associated networking equipment in a Red Hat Cluster are capable of

supporting multicast addresses and IGMP; if they are, ensure that multicast addressing and IGMP

are enabled. Without multicast and IGMP, not all nodes can participate in a cluster, causing the

cluster to fail.

Note

Procedures for configuring network switches and associated networking equipment vary

according each product. Refer to the appropriate vendor documentation or other information

about configuring network switches and associated networking equipment to enable multicast

addresses and IGMP.

Note

IPV6 is not supported for Cluster Suite in Red Hat Enterprise Linux 5.

2.10. Configuring t he ipt ables Firewall t o Allow Clust er Component s

You can use the following filtering to allow multicast traffic through the iptables firewall for the

various cluster components.

For openais, use the following filtering. Port 5405 is used to receive multicast traffic.

iptables -I INPUT -p udp -m state --state NEW -m multiport --dports 5404,5405 -j

For ricci:

iptables -I INPUT -p tcp -m state --state NEW -m multiport --dports 11111 -j ACCEPT

For modcluster:

iptables -I INPUT -p tcp -m state --state NEW -m multiport --dports 16851 -j ACCEPT

⁠Chapt er 2 . Before Config uring a Red Hat Clust er