Exchange Disaster Recovery Tips

You know that someday disaster could strike at your Exchange environment—probably at the worst possible time. Regardless of whether your Exchange organization is large or small, losing mail services has a big impact on your business. These three tips will help you in designing, planning, testing, and implementing an Exchange-specific disaster recovery plan. For additional tips, see the Web-exclusive sidebar "More Exchange Disaster Recovery Tips," http://www.windowsitpro.com/microsoftexchangeoutlook, InstantDoc ID 49606.

Tip 1: Assess Required Service Levels
Email is a vital function, perhaps never more so than when disaster strikes and mail services aren't available. You need to make sure all email users at all levels of the business agree about the response times and service levels needed. Clearly explain to users how IT will restore email services in different disaster scenarios.

Recovery time will depend largely on how long it will take to recover Active Directory (AD), the Exchange system, and Exchange databases from backup media. Therefore, to gauge response time, first calculate the total amount of time needed to recover a complete database and a complete server. Doing so lets you estimate the amount of time needed to recover an Information Store (IS) or a complete server in optimum circumstances. You'll then have to build in additional recovery time for more severe disasters to accommodate dependencies such as faulty or inoperative network infrastructure and other failing services (e.g., SANs, NICs). To shorten recovery time, you might also opt to decrease database sizes, which will almost automatically require additional databases and storage groups (SGs). Each SG, with a maximum of four per server, can have as many as five databases. Because each SG creates its own log files, you'll then want to separate the transaction-log sets on dedicated disks. Spreading the storage load in this way can help you recover the databases more quickly. . . .