How to Setup /m:recoverserver In Exchange 2010 / 2013 to Recover Failed Server
You have installed the Exchange server role and established links with Active Directory. You have also configured monitoring and backup to safeguard the health of Exchange server. But the problem may not be resolved even after taking the due precautionary measures. In case you neglect even the smallest of the monitoring alerts with regard to Exchange Server 2010/2013, it may cause a disaster. How to Setup /m:recoverserver In Exchange 2010 / 2013 to Recover Failed Server

To recover the failed server, you would need to set up /m:recoverserver Exchange in Exchange Server 2010/2013 to restore the mailbox database.
There are situations where the Exchange server shuts down abruptly either due to a bad drive or some other reason, and there is no way to revive the server. In that case, implement a new server with Exchange role and upload the Exchange database.
Build a new Exchange server
Note: The new Exchange server should be a replica of the old server. The server settings should neither be upgraded nor downgraded during installation.
If you want to deploy a physical Exchange server, then procure a server chassis and build a new Windows server instance with same service pack and naming convention as the earlier one and install identical characteristics.
Ensure that the hardware components – Hard Drives and RAM – of the old Exchange server and the newly installed server are identical.
Install the Operating System, Antivirus, and Exchange role
Perform the recovery install of Exchange server. You can do it by installing and running the setup with /m:recoverserver switch.
(Setup /m: RecoverServer or ‘M’ switch is used to recover damaged Exchange server. The M switch informs the server to read the Active Directory’s service application’s configuration information. The Server name should be the same on which the setup is installed. It is only after execution of the command that the files and services are mounted on the server, followed by application of roles and settings on the Exchange server.)
Verify that all steps conclude effectively. If not, then redo.
Join Exchange server to the same domain and copy the Exchange server files at an accessible location. Ensure, you are using the same setup files that were mounted previously.
Click the Command prompt and run the following command:
C:\> setup /mode:recoverserver /IAcceptExchangeServerLicenseTerms
Most custom configurations are restored in AD (abbreviation for Active Directory )such as ‘Directory Settings,’ ‘Location and database names,’ ‘Transport Settings’, etc., but the machine-specific configurations are not installed during server-recovery. In that case, Admins should document the machine specific settings such as SSL Certs, IIS settings, modified Config files or Registry keys, and automate on the newly installed server.
Once the Exchange server settings are installed and verified, the next step is to restore the Exchange database.
Restore Microsoft Exchange Database from Backup

As most Exchange Admins maintain a regular backup of the database, it can be quickly restored on the newly configured Exchange server.
Verify the health of Exchange database backup and start the backup restoration. To check the health status, run the following Eseutil command:
Eseutil /ml “Path of the log files\log prefix”
Once you have verified the health of Exchange 2010/2013 database, start the restoration process.
Enable the Backup Manager command on the backup application and restore by using the steps mentioned in the form.
Sometimes, the backup is not healthy, either due to the incomplete or corrupt or unreachable database, then repair the database using the Microsoft Eseutil utility command.
3a. Soft Recovery with Microsoft utility Eseutil

Note: Before performing the database-recovery, check that the server storage has enough space to mount the newly repaired database.
Eseutil commands are not the best when it comes to repairing the corrupt database, due to the following reasons:
⦁ Need almost double the storage space for database recovery
⦁ Has limitations as the utility cannot repair severely corrupted files
⦁ May result in Exchange database errors
The errors and shortcomings are avoidable! Also, there is no need to install large storage for database recovery.
3b. Recovery with Exchange Recovery Software
Deploy an Exchange Recovery software and start repairing the Exchange database. The software repairs large Exchange database without any data loss and works equally well to repair mailboxes on dismounted or offline EDBs. The Admins can save the EDB files in PST format or better export the mailboxes directly to newly configured Exchange or Office 365 with valid login credentials.
Conclusion
Setup /m: RecoverServer in Exchange 2010, 2013 is good to set up Exchange server when there is an issue. However, M switch is not a complete solution for Exchange server recovery, wherein the switch can set up the server functionalities, but it cannot mount the database. There is a need for additional software to mount the database.
The same process and workflow can be simplified with the help of Exchange database repair software. Software such as Stellar Repair for Exchange repairs the Exchange database on the old Exchange server and exports the mailboxes directly to newly configured Live Exchange server. With this process, the chances of errors are almost nil and there is a significant reduction in server downtime.