Was a real solution to this issue ever provided?
On an ESX6.7 host, we moved a single drive from a NetApp hosted datastore to a local SSD.
As of that moment the whole datastore that the drive used to reside on refuses to backup:
Failed to determine LUN based on Serial Number
we moved the disk back from the SSD to the NetApp DS and backups run great again.
- Increasing the timeout did not help.
- spanning datastores are excluded.
Any help is greatly appreciated as we need the SSD performance for a SQL database