Datacenter Migration : Dos and Don'ts from Performance Testing perspectives .

Dos and Don’ts of Data Center migration:

• Do test your application under the network conditions of the new data center location. Your app can now reside in one data center, yet the backend database can be in on a different data center. This new topology comes with different network latency, propagation delay and bandwidth. Unless you capture the right network conditions and factor them in your tests you will not know how your application will perform.
• Don’t assume that all networks are created equal. Don’t ignore the affects they have on your geographically-distributed users. If you have users login from Sydney, Tokyo, New York or Santiago (or wherever else), each experience will be different and will vary based on the network connectivity.
• Do scale for load. One of your many test scenarios should be to test for heavy loads. This is because you need to determine the scalability impact of multiple end users when server locations change. The performance degradation of this move can be serious—to the point of crashing the servers if you don’t test for heavy load.
• Do continue to analyze. Be a proactive performance engineer. Look at all your apps and see where the performance bottlenecks are. If you moved some apps on a third-party SaaS provider, you have to test for the CDN effect. A simple misconfiguration in the CDN can result in big “pass-through” traffic coming from the CDN cache that will immediately result in performance problems on the original server.
• Do optimize. Now that you’ve become proactive about performance, it is vital to understand the best options you have and optimize for performance without penalties. The whole idea behind the comprehensive analytics is to understand where and why you fail, so you can quickly fix the problems.
• Don’t think you are done with one test. When you optimize—you need to test again. When you change settings—you need to test again. The only way to ensure proper Data Center transformation is to always test again. Remember that network conditions are dynamic for the most part and that change in the network connectivity will for sure affect your app’s performance.
• Lastly and perhaps most important. Do chose the right partner. Just as in any marriage, ups and downs, challenges and outages are all part of the picture, but it’s the partner you have that helps you pull through. So do choose wisely.

Link : https://community.hpe.com/t5/LoadRunner-and-Performance/Data-Center-migration-and-achieving-your-happily-ever-after/ba-p/6925224#.WRqVsYVOIaF