Pre-Deployment Sizing Best Practices
During the infrastructure planning phase for your IT environment, System Center Capacity Planner 2007 can help you create a pre-deployment sizing model. You can use the following best-practice guidelines as you develop your infrastructure plan:
- Identify key scenarios Identify the scenarios in which performance is important and the scenarios that pose the most risk to performance objectives.
For example, suppose you want to deploy Exchange Server 2007 to one Mailbox site that is connected to two client-only sites by a T1 network connection. Users at the client-only sites access their e-mail messages over the T1 connection, so there needs to be sufficient network bandwidth for the e-mail workload. - Identify workload Identify the workload as it applies to each scenario. You can use Capacity Planner to enter workload information to model your scenario. For example, you might have the following workload requirements:
- You need to support 5,000 Outlook Cached users.
- All users send 10 percent of their e-mail to Internet recipients.
- Identify performance objectives Define and enter performance objectives for each of your key scenarios in Capacity Planner. Performance objectives reflect business requirements, such as meeting workload requirements and SLAs, and they usually include the following:
- Response time—For example, Microsoft Outlook Web Access transactions should not take longer than 2 seconds to complete.
- Throughput—For example, the system should support 100 transactions per second.
- Resource utilization—For example, a server should not use more than 50 percent of its available processor power.
- Identify budget and hardware resources Identify your budget, which establishes resource constraints. For example, how many servers can your organization afford? Common resources to consider include the following:
- CPU
- Memory
- Disk usage
- Network usage
- Hardware price
- Allocate budget You can use exported Microsoft Excel workbooks from Capacity Planner to add details about the cost of hardware to help you calculate the budget for the deployment.
In terms of budgeting time and device utilization, latency of transactions and percentage of device utilization is calculated by Capacity Planner. This is done by simulating the server application, hardware devices, and projected user load. - **Evaluate **Evaluate your design against objectives and budget. Repeat this step as often as necessary. You might have to modify your design or allocate your resource budget differently to meet performance objectives.
Capacity Planner can help you accomplish the following tasks:- Modify your design.
- Reevaluate requirements.
- **Validate **Validate your model and estimates. Repeat this step as often as necessary. This is an ongoing activity and includes prototyping, assessing, and measuring.
The further along you are in your project's life cycle, the greater the accuracy of the validation. Validation is based on available benchmarks or on a proof of concept in a lab environment.
You can see examples of how to use Capacity Planner for pre-deployment sizing in the end-to-end scenarios in the following section:
Note
By itself, Capacity Planner does not recommend or provide a deployable architecture. You should independently test and verify any results in a test environment. Other considerations for planning a hardware and software infrastructure deployment, such as availability and security, are not addressed by Capacity Planner.