Exchange 2013 Integrity Check

Question

I have recently run an eseutil integrity check on my exchange 2013 database. I am receiving one particular warning in the log file it produced very frequently. I am not able to find good information on what the warning means. Please see warning below, any insight would be helpful.

WARNING: orphaned LV (lid 18500, refcount 0). Offline defragmentation should fix this.

Answer 1

Hi @Paul Thompson .
Yikes! All 4 at once? :(

For that error - "orphaned LV"- That is an orphaned Long Value in the edb database. Exchange generally takes care of its own housekeeping, so that most likely got orphaned from a server crash or power issue, disk issue etc...
Despite that, that issue should not have caused the DB any issues and is most likely the result of some event rather then the cause.

In all cases, I would never attempt to fix any issue as I mentioned above. I would just move mailboxes to a new database. Its the only sure way to ensure the issue is fixed, its quicker, and will generally fix any problem ( except bad hardware of course :) )

As far as checking the DB integrity, I let Exchange do that with its built in online checks. Since Exchange 2013, its been superior in that regard and actually will attempt to patch itself if the EDB is damaged. The only time it cant fix itself or attempt to is if there is a hardware issue, in which case it will fail and alert in the logs and suggest a reseed.

This is where having a DAG is key. Then you can simply reseed from the other copies. ( You are running a DAG it appears?) Where you not able to reseed from a good copy or did the corruption follow the DB to all the copies?

The other integrity checking option is https://learn.microsoft.com/en-us/powershell/module/exchange/new-mailboxrepairrequest?view=exchange-ps
This is for logical corruption within a DB or mailbox. Its not something you should ever really need to use either unless attempting fix specific issues such as folder counts and things like that. I have probably needed to do this once in the last ten years, so its the exception rather then the norm to run it.
Typically, a mailbox move to another DB is an easier fix :)

Answer 2

Just curious why you ran this in the first place? :)

Honestly, running integrity checks or doing anything with eseutil is really old hat and not something I would even bother with.

If you are experiencing issues, then simply move mailboxes to another database and remove the problematic database.

Answer 3

It was an issue where 4 databases got corrupt at the same time with 90+ accounts. We were able to recover from backups. We have yet to discover what the issue was that corrupt the databases as we have redundant hardware and HA cluster. Either way i respect your opinion as to why we would run eseutil. Can you please let me know what would be a more effective way to find the integrity of our databases and or please answer the original question which no one seems to know the answer to?

Answer 4

Thank you for the explanation that makes much more sense now. I am sorry, I mistyped, we have 90+ accounts in the particular database that is getting the Orphaned LV warning. So, no we don't have a DAG. What would be the risk of leaving the database as is with the orphaned LV errors?