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 Cluster Suite Overview document provides an overview of Red Hat Cluster Suite for Red Hat Enterprise Linux 6. Additionally, the High Availability Administration document describes the configuration and management of Red Hat cluster systems for Red Hat Enterprise Linux 6.
7.1. Corosync Cluster Engine
Red Hat Enterprise Linux 6 utilizes the Corosync Cluster Engine for core cluster functionality.
7.2. Unified Logging Configuration
The various daemons that High Availability employs now utilize a shared unified logging configuration. This allows system administrators to enable, capture and read cluster system logs via a single command in the cluster configuration.
7.3. High Availability Administration
Conga is an integrated set of software components that provides centralized configuration and management for Red Hat Enterprise Linux High Availability. One of the primary components of Conga is luci, a server that runs on one computer and communicates with multiple clusters and computers. In Red Hat Enterprise Linux 6 the web interface that is used to interact with luci has been redesigned.
7.4. General High Availability Improvements
In addition to the features and improvements detailed above, the following features and enhancements to clustering have been implemented for Red Hat Enterprise Linux 6.
Enhanced support for Internet Protocol version 6 (IPv6)
SCSI persistent reservation fencing support is improved.
Virtualized KVM guests can now be run as managed services.