I have a situation with one Exchange 2010 Enterprise, SP1 server that is a member of a four server DAG. All of the DAG members replicate the databases between each other so a copy of the database is on each server. One of the direct access storage towers on one of the DAG members failed (two of the DAG members store their databases on SAN storage, and the third member is also using a DAS tower.
The OS of the server with the failed DAS is intact as the storage tower only stores database copies. The problem is the DAS towers, due to cost when we went to Ex 2010, were set up in a RAID 0 JBOD array. The array failed, so I had to rebuild the disk array configuration and wipe the drives. In the EMC the downed server and databases show "ServiceDown".
So, the next step is to bring up the Exchange server DAG member that is attached and set up the mount points and paths for all the databases as they were before. Again, the OS of the server is fine, so I don't see I need to reinstall Exchange. I figured I do this with the Exchange server services disabled, and the server off the network for the time being.
Once I have the disk storage and database folders set up again, I was going to bring the DAG member online, and figured the EMC will show those databases as "Failed", and then I can reseed them from the other servers. However, I ran the idea by an MS support tech (who really seemed not sure what to do which is why I ask here), and he suggested restoring the databases to the folders on the fixed DAS storage, then enabling the Exchange services on the DAG member. The databases would then show out of sync and reseed them that way. I'm not convinced I need to do a restore of the database files from tape. I can reseed the databases without issue with no tape restore as far as bandwidth goes, but the MS guy seemed to feel it would not work without a version of the database files restored.
For comparison, when we've had a drive failure on this DAS array before, because of the way the drives are set up, we would see one or two failed databases, NOT restore database files from tape and reseed the databases. Even with a complete failure of the DAS, once the original file paths are set up I would think this would theoretically work the same.
The MS tech was even suggesting I run the setup.exe and with the switches to restore the Exchange server, when I've not removed anything from AD configs, nor have had to rebuild the server OS or reinstall Exchange on the server, so I'm not sure the MS guy understood my scenario. Hence why I'm checking here.