VEEAM 6.5 SOAP 503 Service Unavailable and Snapshots

We recently encountered an issue with our nightly backups using VEEAM where our Vcenter was being taken to its knees on CPU.

The symptoms: After about 15 jobs would kick off CPU would spike to 100% regardless of how much resources you give it.

After much troubleshooting and tickets with Vmware and VEEAM we determined that it was being caused by some stale database entries pointing to snapshots in Vcenter that we had removed manually. After VEEAM support cleaned up these entries and replaced a DLL file on the app server we were back in business.

Hope anyone else that may come across this will benefit from knowing what the possible issue is.