Step # 1 - Protect Against Server Failures with Quality Hardware andComponent Redundancy

Server core components include power supplies, fans, memory, CPUs and mainlogic boards. Purchasing robust, name brand servers, performing recommendedpreventative maintenance, and monitoring server errors for signs of futureproblems, can all help reduce the chances of Exchange downtime due tocatastrophic server failure.

Downtime caused by server component failures can be significantly reducedby adding redundancy at the component level. Examples are: redundant powerand cooling, ECC memory, with the ability to correct single-bit memoryerrors, and combining Ethernet cards with RAID.

Step # 2 - Get Rid of Storage Failures with Storage Device Redundancy andRAID

Storage protection relies on device redundancy combined with RAID storagealgorithms to protect data access and data integrity from hardwarefailures. There are distinct issues for both local disk storage and forshared, network storage. For local storage, it is quite easy to add extradisks configured with RAID protection. A second disk controller is alsorequired if you want to protect against controller failures.

Access to shared storage relies on either a fibre channel or Ethernetstorage network. To assure uninterrupted access to shared storage, thesenetworks must be designed to eliminate all single points of failure. Thisrequires redundancy of network paths, network switches, and networkconnections to each storage array.

Step # 3 - Prevent Network Failures with Redundant Network Paths, Switchesand Routers

The network infrastructure itself must be fault-tolerant, consisting ofredundant network paths, switches, routers and other network elements.Server connections can also be duplicated to eliminate failovers caused bythe failure of a single server or network component. Take care to ensurethat the physical network hardware does not share common components. Forexample, dual-ported network cards share common hardware logic, and asingle card failure can disable both ports. Full redundancy requires eithertwo separate adapters or the combination of a built-in network port alongwith a separate network adapter.

Step # 4 - Forget Site Failures with Data Replication to another Site

Site failures can range from an air conditioning failure or a leaking roofthat affects a single building, a power failure that affects a limitedlocal area, or a major hurricane that affects a large geographic area. Sitedisruptions can last anywhere from a few hours to days or even weeks.

There are two methods for dealing with site disasters. One method is totightly couple redundant servers across high speed/low latency links, toprovide zero data-loss and zero downtime. The other method is to looselycouple redundant servers over medium speed/higher latency/greater distancelines, to provide a disaster recovery (DR) capability where a remote servercan be restarted with a copy of the application database, which only missesthe last few updates. In the latter case, asynchronous data replication isused to keep a backup copy of the data.

Data replication is combined with error detection and failover tools tohelp get a disaster recovery site up and running in minutes or hours,rather than days.

Step # 5 - Consider Virtualizing Exchange for Better High Availability

The latest server virtualization technologies, while not required forprotecting Exchange, do offer some unique benefits that can make Exchangeprotection both easier and more effective. Virtualization makes it veryeasy to set up evaluation test and development environments without theneed for additional, dedicated hardware. Virtualization also allowsresources to be adjusted dynamically to accommodate growth or peak loads.

For more on how the latest virtualization technologies makes it easier forIT to keep users continuously connected to Microsoft Exchange, register onlinefor the webinar, Virtualizing Exchange - The Cold, Hard Numbers on WhyCitrix XenServer + everRun VM is the Best Platform, hosted by MarathonTechnologies and Citrix Systems on November 11.

About Marathon Technologies

With more than 2000 global customers, Marathon is the world's first andonly provider of fault-tolerant, automated, high availability and disasterrecovery software for physical and virtual servers. Marathon's everRun®software prevents outages and data loss -- without IT intervention.Organizations using everRun achieve continuous availability, 100% dataprotection, and rapid disaster recovery -- all through "one-click"operation. In the past year, the company has been awarded eleven majorindustry accolades including the "Best of VMworld 2007 - New Technology" award for bringingfault-tolerant, high availability to virtual servers. CIO.com namedMarathon Technologies one of "10 Virtualization Vendors to Watch in 2008." The company wasalso recognized as a 2008 Computerworld Honors Program Laureate and named a winnerin eWEEK's Eighth AnnualExcellence Awards Program. For more information visitwww.marathontechnologies.com.

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Contacts:Brian Keith MullinsMarathon Technologies Corp.978.489.1146bmullins@marathontechnologies.comLynda SylviaRacepoint Group Inc.781.487.4619lsylvia@racepointgroup.com