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4.3. Clustering and High Availability

luci support for fence_sanlock
The luci tool now supports the sanlock fence agent as a Technology Preview. The agent is available in the luci's list of agents.
Package: luci-0.26.0-48
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-
The keepalived package has been included as a Technology Preview, starting with Red Hat Enterprise Linux 6.4. 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. The haproxy package is included as a Technology Preview, starting with Red Hat Enterprise Linux 6.4.
Package: haproxy-1.4.24-2