Red Hat Training

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

Chapter 9. Clustering

Clusters are multiple computers (nodes) working together to increase reliability, scalability, and availability to critical production services. High Availability using Red Hat Enterprise Linux 7 can be deployed in a variety of configurations to suit varying needs for performance, high-availability, load balancing, and file sharing.
Refer to Section 19.5, “Clustering and High Availability” for a list of documents available for Red Hat Enterprise Linux 7 providing information about configuration and management of Red Hat High Availability Add-On.

9.1. Pacemaker Cluster Manager

Red Hat Enterprise Linux 7 replaces rgmanager with Pacemaker for managing cluster resources and recovering from node failures.
Some of the benefits of Pacemaker include:
  • Automatic synchronization and versioning of the resource configuration;
  • A flexible resource and fencing model that can more closely match the user's environment;
  • Fencing can be used to recover from resource-level failures;
  • Time-based configuration options;
  • The ability to run the same resource on multiple nodes. For example, a web server or cluster file system;
  • The ability to run the same resource on multiple nodes in one of two different modes. For example, a sync source and target;
  • Pacemaker does not require a distributed lock manager;
  • Configurable behavior when quorum is lost or multiple partitions are formed.