Red Hat Training

A Red Hat training course is available for Red Hat Enterprise Linux

4.3. Clustering and High Availability

The pcs package has been added to Red Hat Enterprise Linux 6 as a Technology Preview. This package provides a command-line tool configure and manage the corosync and pacemaker utilities.
Package: pcs-0.9.26-10
luci support for fence_sanlock
The luci tool now supports the Sanlock fence agent as a Technology Preview, which is available in the luci's list of agents.
Package: luci-0.26.0-37
Recovering a node via a hardware watchdog device
New fence_sanlock agent and checkquorum.wdmd, included in Red Hat Enterprise Linux 6.4 as a Technology Preview, provide new mechanisms to trigger the recovery of a node via a hardware watchdog device. Tutorials on how to enable this Technology Preview will be available at
Note that SELinux in enforcing mode is currently not supported.
Package: cluster-
Red Hat Enterprise Linux 6.4 includes the keepalived package as a Technology Preview. The keepalived package provides simple and robust facilities for load-balancing and high-availability. The load-balancing framework relies on the well-know and widely used Linux Virtual Server kernel module providing Layer4 network load-balancing. The keepalived daemon implements a set of health checkers to load-balanced server pools according to their state. The keepalived daemon also implements the Virtual Router Redundancy Protocol (VRRP), allowing router or director failover to achieve high availability.
Package: keepalived-1.2.7-3
HAProxy is a stand-alone, layer-7, high-performance network load balancer for TCP and HTTP-based applications which can perform various types of scheduling based on the content of the HTTP requests. Red Hat Enterprise Linux 6.4 introduces the haproxy package as a Technology Preview.
Package: haproxy-1.4.22-3
libqb package
The libqb package provides a library with the primary purpose of providing high performance client server reusable features, such as high performance logging, tracing, inter-process communication, and polling. This package is introduced as a dependency of the pacemaker package, and is considered a Technology Preview.
Package: libqb-0.14.2-3
pacemaker, BZ#456895
Pacemaker, a scalable high-availability cluster resource manager, is included in Red Hat Enterprise Linux 6 as a Technology Preview. Pacemaker is not fully integrated with the Red Hat cluster stack.
Package: pacemaker-1.1.8-7