HI

my exchange server 2010 has database mounting prob. suddenly power shutdown and server restart after that a database goes in dismount state and when i try to mount the database it is showing  the log file missing error and can not mount. kindly help me to solve this problem.

Sunit  

• does the error show you which log file is missing?
• If so is that log file present?  if not you might check to see if its been quarantined by your anti virus program.
• if the file is present then it very well may be damaged and in that case you can either run a repair against that database, or restore from backup.

If the logs were deleted or damaged and are non-recoverable then you need to

1. Check the state of the DB by running Eseutil /MH against the db. Check out this article here which will also give you commands to do a rollup or repair http://blogs.technet.com/b/mspfe/archive/2012/09/06/why-exchange-databases-might-remain-dirty-after-eseutil-r-recovery.aspx

2. If it reamins DIRTY/INCONSISTENT and then you really only have three options.

NOTE: Before you do anything else make a MASTER copy of the EDB that you are having issues with and never use it for recovery other then to make a WORKING copy of that EDB so that if something goes wrong with the WORKING copy you have the MASTER copy available to make a new WORKING copy.

OPTION A: You can create a dial-tone database to get your users up a running right away and then once up and operational you can then use a WORKING copy of EDB to do data recovery via the the MS RDB or use Lucid8's DigiScope http://www.lucid8.com/product/digiscope.asp to open that offline WORKING copy EDB to recover any missing/delta data into the production exchange server.  To do this you would

1. Rename or remove the EDB and associated log files.  Personally I would recommend that you just rename the directory/folder they are in i.e. if they are located in  "U:\Program Files\Microsoft\Exchange Server\V14\Mailbox\Users_A-F"  you would rename the "Users_A-F" to say "Old_Users_A-F" and then create a new "Users_A-F" directory

2. Then go into the EMC and mount the DB

3. Exchange will tell you that it cannot find the database files and that if you continue you it will create a new blank database

4. Say yes and a new blank database is created and now users can send and receive new emails, HOWEVER they will not have any of their historical email (yet)

5. Now open that WORKING copy database using Lucid8's DigiScope http://www.lucid8.com/product/digiscope.asp and restore the historical data into the production server.

NOTE 1: Since the DB is damaged or missing log files DigiScope will give you the option of REPAIRING the database or to do a FORENSIC Mount.  Always try the Forensic Mount first since if possible it will just open the DB so that you can do a recovery without having to wait for a lengthy repair process.

NOTE 2 : restoration of data from the WORKING copy via DigiScope can be done while users are working within Outlook.

OPTION B: You can recover from your last known good backup.  Once up and operational you can then use a WORKING copy of EDB to do data recovery via the the MS RDB or use Lucid8's DigiScope http://www.lucid8.com/product/digiscope.asp to open that offline WORKING copy EDB to recover any missing/delta data into the production exchange server.

OPTION C: The other option is to run eseutil /P against the DB as outlined in the above article in order to make it clean/consistent and mountable.   If you choose this method then;

1. Ensure that you keep a MASTER copy of the old EDB and only take action against the WORKING copy

2. Once mounted again I would highly recommend that you create a new mailbox DB and then move the mailboxes from the repaired EDB into the NEW mailbox EDB.  While the repaired EDB may operate without issue, historically once a DB has been hard repaired with a /P you want to get your mailboxes off of it ASAP.