Clusters are multiple computers (nodes) working in concert to increase reliability, scalability, and availability to critical production services. High Availability using Red Hat Enterprise Linux 6 can be deployed in a variety of configurations to suit varying needs for performance, high-availability, load balancing, and file sharing.
The following major updates to clustering are available in Red Hat Enterprise Linux 6.1
Rgmanager now supports the concept of critical and non-critical resources
System Administrators can now configure and run a cluster using command line tools. This feature provides an alternative to manually editing the cluster.conf configuration file or using the graphical configuration tool, Luci.
Red Hat Enterprise Linux High Availability on Red Hat Enterprise Linux KVM hosts is fully supported
Comprehensive SNMP Trap support from central cluster daemons and sub-parts
Additional watchdog integration allows a node to reboot itself when it loses quorum
The development library packages provided in the High Availability, Load Balancer, and Resilient Storage Add-On channels are not considered supported nor are their ABIs or APIs guaranteed to be consistent.
The Cluster Administration
document describes the configuration and management of Red Hat cluster systems for Red Hat Enterprise Linux 6.