Caching the results of DPM explored maschines is very useful, especially if you have lots of them, and Michael Seidls Blog TechGuy.at showed me something I missed during TechEd.
The DPM results coming from a WMI querys but with a small reg hack they will be cached.
If you switch to HKLM\SOFTWARE\Microsoft Data Protection Manager\Configuration you have to put in the key “CacheInquiryResults”.
Restart the DPM console and you will find a clear cache button in the select group members section.
Another reg key value is “InquiryResultsTimeoutInterval”.
Microsofts Technet Site says for both together:
When you are protecting a large number (over 200 virtual machines) of virtual machines using cluster shared volumes (CSV), it may take a long time (>15 min) to populate the inquiry screen in the Create New Protection Group Wizard. You can avoid this by enabling caching on the primary DPM server. After you enable caching, when you expand the data source on the inquiry screen, DPM will refresh the resource groups under that node, but the virtual machines under each resource group will be populated from the cache. The default time-out for the cache is 48 hours. You can change this by editing the registry.
To enable caching, create a new registry key called CacheInquiryResults at HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft Data Protection Manager\Configuration. Under this key, create the DWORD InquiryResultsTimeoutInterval.
After you create the registry key, you will see the Clear Cache button on the inquiry page of the Create New Protection Group Wizard. Click this button when you want to force DPM to refresh the list of virtual machines.
TechGuy.at – german:
MS Technet – english: