So we have just migrated our users over to Exchange 2010 a couple of months ago. When we started we purchased a new server and set it up with Windows 2008 R2 and Exchange 2010. The plan was to migrate all of our users from the old Exchange 2007 server to the new Exchange 2010 and then rebuild the old one with Exchange 2010 also so we could take advantage of the new DAG options. It all sounded easy enough.
When we setup the new server we went ahead and configured all of the DAG settings, but it just contained the single server for the time being. Once we got everyone moved we rebuilt the old server and got everything patched to the same level. Then we tried to add a database copy for an existing DB to the newly rebuilt server, but got some strange messages about missing log files when the copy was created and we could never get the copy to a “Healthy” state. If we created a new database and added a copy it would work just fine. Also, we did finally get one of the existing DB’s to establish a healthy copy. So we started thinking we had a network problem.
We looked at the network and couldn’t find anything going on. We finally called Microsoft and discovered a quick simple solution.
We were instructed to do the following:
1. Dismount the active database.
2. Move the Log files to a different location.
3. Mount the database.
4. Add the database copy to the second server.
After performing these steps everything worked as expected. The DAG should the active copy as “Mounted” and the passive copy as “Healthy”.
Microsoft then recommended getting a good full backup before deleting the log files that were moved.
