A Critical Component of Data Protection & Business Continuance

Published in Sirius Connect, 2Q2007; Copyright 2007 Sirius Computer Solutions   IT organizations of all sizes are increasingly recognizing the need for 24x7 operations where scheduled outages for maintenance are measured in minutes per year. The tragic events of 9/11, and other more recent disasters, such as Hurricane Katrina, have brought the business continuity exposures of a single data center into sharp relief. Sirius is helping many of these organizations to assess, develop, deliver, and implement solutions that provide data protection and business continuance for their entire environment. Sirius offers a wide range of IBM and Network Appliance (NetApp) storage solutions for business continuance, including disk, tape, and virtualization-based replication/mirroring.

For help with disk mirroring, data protection, or business continuance in your environment:

In the last Sirius Connect, we started the conversation on disk mirroring in “Start Simple with SnapMirror and Snapshot ... Supporting high data availability and quick recovery for mission-critical applications.” In this issue, we discuss the disk mirroring solutions for business continuance from an enterprise perspective - where the term enterprise is intended to denote the scope of the solution. Enterprise solutions are designed to provide a single enterprise-wide solution for all IBM platforms (System z, i, p, x and BladeCenter), as well as non-IBM environments running Solaris, Windows, Linux, HP-UX, and others.

IBM System Storage DS Series Disk Mirroring Solutions
The IBM DS8000 series offers a set of industry-leading disk mirroring solutions, collectively known as Remote Mirror and Copy (RMC). Within the RMC family are three primary modes of operation: Metro Mirror, Global Mirror and Global Copy.  These may be combined to provide even greater flexibility and data protection options, such as Metro/Global Mirror.

Metro Mirror is a synchronous (real-time) remote data-mirroring technique, designed to constantly maintain an up-to-date copy of the local application data at a remote site within a metropolitan area (typically up to 300 km away). With Metro Mirror, absolute data currency and consistency is maintained between sites at longer supported distances and with better performance than competing storage offerings.

Global Mirror is an asynchronous two-site remote data-mirroring solution designed to maintain a complete and consistent remote mirror of data at virtually unlimited distances with next to no application response time degradation. Separating data centers by longer distances helps to provide protection from regional outages. This asynchronous technique can help you achieve better performance at unlimited distances by allowing the secondary site to trail in currency a few seconds behind the primary site. With Global Mirror, currency can be configured to be as little as three to five seconds with respect to the host I/O. Global Mirror consistency groups support an intermix of mainframe and open server data, and can be created across up to eight DS8000 series systems, DS6000TM series systems, or IBM Enterprise Storage Server (ESS or "Shark") systems, allowing scalability for application growth. Global Mirror incorporates numerous IBM patented technologies that ensure data consistency, while providing the best performance with the lowest overall solution cost, complexity, and resource requirements.

Global Copy is a non-synchronous, remote copy function that is ideally suited for remote data migration, off-site backups, and transmission of inactive database logs at virtually unlimited distances.

Metro/Global Mirror is a three-site asynchronous solution that combines Metro and Global Mirror technologies to provide the highest levels of multi-site business continuance. While the Metro Mirror synchronously mirrors data to a second site within the metropolitan area, the Global Mirror asynchronously mirrors data to a separate remote site that may be at global distance away from the secondary site. This way, the recoverability benefits of synchronous mirroring (no data loss and near-immediate remote data availability) are combined with the added protection against regional events through the cascaded asynchronous mirroring to a second recovery site.

IBM System Storage Resiliency Automation
These storage-based data mirroring solutions are augmented by automation software. IBM TotalStorage Productivity Center for Replication provides a single administrative and management interface for the IBM DS series disk systems and  the associated copy and mirroring functions such as FlashCopy, Metro Mirror, and Global Mirror.

Sirius and IBM also offer a comprehensive set of integrated automation solutions for IBM System z with Geographically Dispersed Parallel Sysplex (GDPS) integration, for System p through tight integration with HACMP/XD, for System i with Lakeview Technology’s MIMIX solutions, and for System x clustered Windows environments with IBM Geographically Dispersed Sites for Microsoft Cluster Services.

Although the focus of this article is on disk-mirroring, this is only one critical component in an organization's overall data protection/business continuance strategy. Sirius has a breadth of expertise in the form of solution architects and solutions implementation professionals, who can put together a complete solution that encompasses servers, networks, storage and automation, for a truly round-the-clock IT environment. Contact your Sirius account executive to learn more about how Sirius can help you and your team put together an exceptional business continuance solution that balances cost-effectiveness with your business recovery objectives.