Hi guys, I am relatively new in MS Exchange. I have an Exchange organization running since last December. The company I admin for is quite small. We only have about 90 users. Initially, when installing Exchange, I created a single Mailbox Database. Now that its size is approaching 50Gb I am getting a bit worried. I heard many times that the best practice would be keeping a DB at a manageable size by creating a new one every time the current DB reaches a certain limit. My question is how I can perform this in practice. OK, for sure I know how to create another Mailbox DB and mount it. But how can I tell Exchange to use the new one as a DB for mail delivery? Will the newly created DB get a copy of user folder structure automatically and become a default DB for storing all user messages since then? Will Exchange keep all mounted databases and track user message locations automatically or will I have to configure something manually? In general, how the whole thing is usually done? Sorry for my dummy's questions. I would be really grateful if you guys could shed some light on it for me. Many thanks. Serge.

Hello Serge, You can move certain user mailboxes from one database to another.After move user mailbox attribute set according to the database it belongs, you dont need do any configuration changes. Which version of Exchange you are using?.Refer below for Exchange 2007. Use this link to create new mailbox database.http://technet.microsoft.com/en-us/library/bb201716(EXCHG.80).aspx & to move user mailboxes refer to this http://technet.microsoft.com/en-us/library/aa997961(EXCHG.80).aspx from one database to another. Hope it helps.

Mango_derek, Thanks for help. I am using Exchange 2010. So, as I understand, each mailbox belongs to a certain DB. And there is no way spreading the contents of a mailbox to several DBs so that messages started to get saved in another DB at certain point. Right? Let's assume the amount of users doesn't change over time. But the mailboxes, of course, keep growing. Is there the only way of keeping mailbox DBs manageable by moving some users over to a new DB from old ones every time? With this concept we seem to come to one DB per user at some point in time. I feel there should be another typical solution to this problem, some "best practice".. Thank you.

Hello Yes each mailbox belongs to a certain DB only at any given time. **********And there is no way spreading the contents of a mailbox to several DBs so that messages started to get saved in another DB at certain point. Right?******* >>Refer link http://technet.microsoft.com/en-us/library/dd979795.aspx by which you can configure personal archive for a mailbox which can be place on different DB if you wish to. Let me know if you need any help in understanding archiving .

Hi, I would consider to build a Database Availability Group to support your increasing mailbox database. With the significant core improvements made to Exchange 2010, the maximum recommended mailbox database size when using continuous replication has increased from 200 gigabytes (GB) in Exchange 2007 to 2 terabytes in Exchange 2010. For more information: http://www.msexchange.org/articles_tutorials/exchange-server-2010/high-availability-recovery/uncovering-exchange-2010-database-availability-groups-dags-part1.html Of course, derek's advice is pretty good. I just provide another suggestion for you.Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.