Readers often ask me for advice about defining service level agreements (SLAs) for their Exchange Server deployments. SLAs are one of the few means we have to ensure that our Exchange deployments deliver business value to our organization by helping the organization meet business objectives. SLAs will differ for every corporate environment, so let's look at the process I recommend for Exchange SLA definition.
Typically, Exchange SLAs fall into four categories: performance, disaster recovery, security, and management. Performance SLAs deal with message delivery or response-time metrics. These SLAs typically follow the form, "Ninety-five percent of messages will be delivered worldwide within 15 minutes." In some cases, the SLA defines the other 5 percent (i.e., the remaining 5 percent will be delivered within 30 minutes). Disaster-recovery SLAs usually concern how long it takes to get data back when disaster strikes and data is lost. Disaster recovery SLAs might focus on recovery times for an entire server or be more granular, such as providing guaranteed recovery times for an information store (IS), a mailbox, or even an individual item in a folder. Security SLAs generally include virus-detection rate assurances or encryption performance assurances. Management SLAs help Exchange deployments meet user and account maintenance requirements.
SLA definition for Exchange is a four-step process: SLA planning, SLA development, SLA deployment, and SLA review. SLA planning is the most crucial step and sets the stage for the entire process. You need to get the right people from the right business areas involved in the SLA-planning process. During this SLA planning phase, you attempt to comprehend your organization's business activities and how the various groups rely on Exchange services to accomplish those activities. This knowledge reveals just how important Exchange is to your business.
SLA development translates business requirements for Exchange services into measurable, realistic, and cost-effective SLAs. You need to define an SLA for each of the four key categories (performance, disaster recovery, security, and management). The resulting SLAs must be consensus-based and clearly demonstrate how the Exchange deployment will help deliver business objectives.
Deploying your Exchange SLAs involves converting your SLA planning documents (developed in step two) into tangible units of management and operational activity. This step requires that you have the necessary infrastructure, tools, training, and reporting mechanisms in place to fulfill the SLA.
After you've planned, developed, and deployed your Exchange SLAs, you must periodically review them to ensure that they're achieving desired results (supporting business objectives). You must also be certain that your SLAs remain realistic, measurable, and cost effective. This feedback loop ensures that your Exchange deployment continues to deliver business value to the organization.
The SLA-definition process will differ depending on your organizational culture, business objectives, and your IT staff's operational approach. With this simple four-step process for Exchange SLA definition, you can be on the road to establishing ideal SLAs for your Exchange deployment. Good luck!