Call “StorageResourceManager.RecommendDatastores” for object “StorageResourceManager” on vCenter Server failed

If you are using Datastore cluster with enabled SDRS in vSphere 5.1 you possible will receive this error message.

Call “StorageResourceManager.RecommendDatastores” for object “StorageResourceManager” on vCenter Server failed

Currently is no fix available from VMware. But will possible be available in ESXi 5.1 Update 1. There is a workaround available described in the VMware KB. Link

To work around this issue:
Disable Storage DRS. To disable Storage DRS:

In the vSphere Client inventory, right-click a datastore cluster and select Edit Settings.
Select Turn off Storage DRS and click OK.

Clone the virtual machine from the template.
Enable Storage DRS. To enable Storage DRS:

In the vSphere Client inventory, right-click a datastore cluster and select Edit Settings.
Select Turn on Storage DRS and click OK.