We are migrating a few ESXi hosts to a different vCenter and would like to retain the historical performance data from the existing vCenter. Can we save this data and refer to it when needed?
The performance data for vCenter Server is stored in a SQL database. If you want to migrate vCenter Server from one host to another, the process is rather well documented. This will move your data from one host to another. Sadly, doing more complicated things with the data is far more difficult.
If you are moving an ESXi host from one vCenter to another, the performance data doesn't follow. To make the migration work, you need to fully detach the host from the old vCenter and rejoin it to the new one; otherwise, performance statistics collection may fail.
You can export the data into an Excel spreadsheet before the move. You can also do this through PowerCLI. Additionally, you might consider investigating third-party applications -- such as CloudPhysics -- that pull information out of vCenter and run various analytics on them. This won't help with historic data, but it should help with future issues.
Newer installations will be able to gain a better look at historic data via Log Insight, now integrated with vCenter Operations Manager , or vCOPs, starting with version 5.7.1.
For now, the feature we really want -- to have our vCenter performance history follow our hosts from vCenter to vCenter -- isn't available. Fortunately, PowerCLI and the vCenter APIs are powerful. You can extract a lot of information on your own or find a third-party app to do just about anything.
This was first published in October 2013