In a volatile and technology-dependent business climate, downtime, whether it is planned or unplanned, is costly. High availability and data protection are not new concepts to IT professionals. What is new are the expanding options and capabilities around deployment of highly available environments that offer varying levels of data, application and infrastructure resilience.

Many tiers of a high availability disaster recovery (HADR) solution are possible. The right HADR configuration is a balance between recovery time requirements and cost. Critical decisions must be made to determine which services within the business must remain online in order to continue operations.

IBM® Power Systems customers who use AIX® (UNIX®) and IBM i operating systems already benefit from the industry-leading resiliency capabilities (reliability, availability, and serviceability (RAS)) of the platform. These customers can further benefit from the continuous availability offered by the IBM PowerHA™ SystemMirror solution. Power Systems servers have become the platform of choice for clients who are running their business-critical workloads. Vital transactions, such as bank deposits, medical claims, logistics of critical goods shipments and benefit payments, are processed every day in IBM AIX and IBM i environments all over the world.

In this IBM Redguide™ publication, we define the fundamental concepts for high availability, present considerations for building a strategy, and make suggestions for choosing an effective high availability and disaster recovery strategy depending on your environment. We offer details about how IBM PowerHA SystemMirror tightly integrates with the Power Systems servers, IBM operating systems, and storage to help meet business continuity requirements. We also discuss the challenges posed by a myriad of environmental risks, changing business environments, and compliance issues.

This document is a reference guide, with a definitive collection of approaches, that outlines high availability offerings from IBM and includes characteristics and respective requirements. The intended audience for this paper is both customers and consultants who are looking for an overview of high availability solution approaches specifically for Power Systems environments.

Overview

What is high availability?

The need for high availability and disaster recovery solutions

Establishing common requirements

Outage types to consider

End-to-end solution components

Application data resiliency: Methods and characteristics

Application infrastructure resiliency

Cluster-aware operating systems

Application-state resiliency

Application friendly cluster infrastructure

Solution options for Power Systems clients