/ Chapter 1. Conceptual Overview | ||||
|---|---|---|---|---|
 | Part I. Installation and Setup | 1.2. Product Benefits |  | |
/ Chapter 1. Conceptual Overview | ||||
|---|---|---|---|---|
| Part I. Installation and Setup | 1.2. Product Benefits | | |
Contents
Abstract
SUSE® Linux Enterprise High Availability Extension is an integrated suite of open source clustering technologies that enables you to implement highly available physical and virtual Linux clusters, and to eliminate single points of failure. It ensures high availability and manageability of critical network resources including data, applications, and services. Thus, it helps you maintain business continuity, protect data integrity, and reduce unplanned downtime for your mission-critical Linux workloads.
It ships with essential monitoring, messaging, and cluster resource management functionality, supporting failover, failback, and migration (load balancing) of individually managed cluster resources. The High Availability Extension is available as add-on to SUSE Linux Enterprise Server 11.
SUSE® Linux Enterprise High Availability Extension helps you ensure and manage the availability of your network resources. The following list highlights some of the key features:
Including active/active and active/passive (N+1, N+M, N to 1, N to M) scenarios, as well as hybrid physical and virtual clusters (allowing virtual servers to be clustered with physical servers to improve services availability and resource utilization).
Multi-node active cluster, containing up to 16 Linux servers. Any server in the cluster can restart resources (applications, services, IP addresses, and file systems) from a failed server in the cluster.
The High Availability Extension ships with OpenAIS messaging and membership layer and Pacemaker Cluster Resource Manager. Using Pacemaker, administrators can continuously monitor the health of their resources, manage dependencies, and automatically stop and start services based on highly configurable rules and policies. The High Availability Extension allows you to tailor a cluster to the specific applications and hardware infrastructure that fit your organization. Time-dependent configuration enables services to automatically migrate back to repaired nodes at specified times.
With the High Availability Extension you can dynamically assign and reassign server storage as needed. It supports Fibre Channel or iSCSI storage area networks (SANs). Shared disk systems are also supported, but they are not a requirement. SUSE Linux Enterprise High Availability Extension also comes with a cluster-aware file system (Oracle Cluster File System, OCFS2) and volume manager (clustered Logical Volume Manager, cLVM). For replication of your data, the High Availability Extension also delivers DRBD (Distributed Replicated Block Device) which you can use to mirror the data of a high availably service from the active node of a cluster to its standby node.
SUSE Linux Enterprise High Availability Extension supports the mixed clustering of both physical and virtual Linux servers. SUSE Linux Enterprise Server 11 ships with Xen, an open source virtualization hypervisor. The cluster resource manager in the High Availability Extension is able to recognize, monitor and manage services running within virtual servers created with Xen, as well as services running in physical servers. Guest systems can be managed as services by the cluster.
SUSE Linux Enterprise High Availability Extension includes a huge number of resource agents to manage a resources such as Apache, IPv4, IPv6 and many more. It also ships with resource agents for popular third party applications such as IBM WebSphere Application Server. For a list of Open Cluster Framework (OCF) resource agents included with your product, refer to Chapter 15, HA OCF Agents. The most up to date list is available online at www.novell.com/products/highavailability.
For easy configuration and administration, the High Availability Extension ships with both a graphical user interface (like YaST and the Linux HA Management Client) and a powerful unified command line interface. Both approaches provide a single point of administration for effectively monitoring and administrating your cluster. Learn how to do so in the following chapters.
