How to Mount / Dismount Database in Exchange 2019, 2016, 2013, and 2010?
Summary: There are situations where, as an Exchange Server administrator you must mount or dismount databases in various Exchange Server versions, such as 2019, 2016, 2013, or 2010. It might be due to an unexpected shutdown of the Exchange server, routine maintenance, or troubleshooting. However, if mounting or dismounting is not performed systematically, it throws various error messages and can lead to business downtime. Thus, we have provided a step-by-step guide for the same.
What is a Database in Microsoft Exchange Server?
It is a mailbox database, where the Exchange Server stores all the respective data which includes Emails, Contacts, Calendars, and Tasks. The main repository file of the Microsoft Exchange Server database is the EDB file that it uses to store user mailbox data as well as public folders. Each database consists of a .edb file (the storage engine database), and a .log file (tracks the changes for recovery).
Mounting vs Dismounting
Mounting the Exchange database simply means making it accessible and active to users. The users can then send and receive emails and can access their contacts, calendars, tasks, etc.
Dismounting the Exchange Server database means, making it unavailable or inactive for users. When administrators dismount the database it comes offline and mailbox access is halted.
Here is the detailed comparison of Mounting vs Dismounting Exchange Database
| Aspect | Mounting | Dismounting |
|---|---|---|
| Status | Online and active | Offline and inactive |
| User Access | Mailboxes accessible | Mailboxes inaccessible |
| Purpose | Make data available to users | Perform maintenance or troubleshoot issues |
| Transaction Logs | Continuously generated and committed | No new logs generated |
| Email Flow | Normal email flow | Email flow to mailboxes in that database stops |
| Impact on Users | None (users can access their data) | Users experience downtime |
| Typical Use Cases | After server restart, post-maintenance, or recovery | Database repair, migration, backup, or troubleshooting |
Possible Reasons for Dismounting Database in Exchange Server
There are several reasons for dismounting the database in the Exchange Server version. Check out the most common and recurring reasons listed below.
- Routine maintenance and troubleshooting.
- Exceeding storage space or storage quota limits reached.
- EDB database corruption or issues in Log files.
- Network or hardware failure; (SAN/NAS) connectivity issues.
- Expired Exchange server license or compliance issues.
- Dirty Shutdown or unexpected restart of the Exchange server.
- Cyber attacks such as Malware or virus intrusion.
- Replication issues in Active Directory or DNS Resolution failure Issues.
- Server resource failure such as running out of memory or CPU.
Methods to Mount and Dismount Database in Exchange Server 2019, 2016, 2013, 2010
If you have admin access, then you can use the Exchange Admin Center. However, you must note that you can only dismount or mount only a single Exchange database at a time. However, with PowerShell, you can mount or dismount multiple databases.
How to Mount Database in Exchange Server via EAC & PowerShell?
The steps are the same for Exchange Server 2019, 2016, and 2013, but for Exchange Server 2010, you have to use the EMC (Exchange Management Console).
Mounting Exchange 2019, 2016, and 2013: Using EAC
Step 1. Open your preferred browser and navigate to – https://<ExchangeServerFQDN>/ecp
Step 2. Use your Exchange admin credentials to log in. Click on the Servers > Select Databases. From the given list of dismounted databases (status shown in the Mounted column).
Step 3. Select the Exchange database that you want to mount > Click on the “…” button > Select the Mount option.
Step 4. Select the Yes button to confirm.
For Dismounting
Step 1. From the same screen (in the Database section), choose the mounted database that you want to dismount.
Step 2. Hit the three dots icons (“…” ) and click on Dismount. Confirm by clicking on yes.
Step 3. Select the Yes button to confirm.
Step 4. Finally, your mailbox database is dismounted successfully.
Note: In EAC users can only mount or dismount mailbox database Exchange one at a time and it makes this method slower as compared to Exchange PowerShell.
For Exchange 2010 Mounting Database: Using EMC
Step 1. From the start menu, launch the Exchange Management Console.
Step 2. Go to Organizational Configuration and expand it. Then select Mailbox.
Step 3. Navigate to the Database Management and open it. Here you will find the list of dismounted databases. Right-click on the Exchange database that you want to mount. Confirm by clicking on yes.
For Dismounting Exchange 2010
Step 1. Right-click on the mounted Exchange database that you want to dismount. Click on Dismount database.
Step 2. Select the Yes button to confirm.
Mount / Dismount Multiple Databases in Exchange Using PowerShell
This method is best suited if you have multiple Exchange databases to handle and want to execute the process efficiently. However, you need to have complete technical knowledge of running PowerShell commands to perform the task.
Mount Exchange Database Using PowerShell cmdlet
This is a step-by-step process and needs to be performed systematically. Please make sure that you execute all these steps to have an error-free experience.
Step 1. Assign Required Roles
To dismount or mount a database in Exchange Server 2019, 2016, 2013, or 2010, you must have a Mailbox Database Management role assigned to your account. If you are an Exchange administrator, this role is by default assigned to you. However, if you don’t have administrator access, you have to assign this permission to yourself.
Run this command in Exchange Management Shell to assign this role:
New-ManagementRoleAssignment -Role "Mailbox Database Management" -User Mohit
Step 2. Identify the Database Name
Before mounting or dismounting the database, you must know the name of the Exchange database. You can either use Exchange Admin Center or PowerShell command to find it.
In Exchange Admin Center:
Open EAC and then go to Servers >> Databases.
In PowerShell cmdlet:
Get-MailboxDatabase
It will list all the mailbox databases along with their names from your Exchange server.
Step 3. Verify Database Status
It is essential to first check status of the database before mounting it to Exchange Server. You can use the below-mentioned procedure for the same.
You can use the Get-MailboxDatabase and Format-Table parameter to get the desired details.
Get-MailboxDatabase –Identity <database name> -Status | Format-Table Name, BackupInProgress, OnlineMaintenanceInProgress
You can also check the status of all databases in one go using the –Server parameter.
Get-MailboxDatabase –Server <server name> -Status | Format-Table Name, BackupInProgress, OnlineMaintenanceInProgress
Step 4. Check Database Health Using eseutil /mh
Along with this, you also need to check if the database is in healthy state or not. You can use the eseutil /mh command to check the health of that database.
eseutil /mh <full path to the edb file>
Once you run this command, you will either get a clean shutdown state or an Exchange Database Dirty Shutdown state.
In case of a dirty shutdown, you need to fix it first before trying the mount the database.
Important Note: If you are facing corruption issues in the Exchange database file and unable to mount Exchange database, then you must try this Exchange Database Recovery Tool. This software is extensively tried and tested by experts and helps users repair EDB files without any data loss.
You can download this application on Windows OS and perform recovery in a hassle free manner.
Once the database is in a healthy state and you know the database name and status, you can now mount the Exchange database.
Step 5. Mount the Exchange Database
This command will mount the specified database without confirmation.
Mount a Single Database:
The PowerShell command to mount a single database in Exchange Server is:
Mount-Database –Identity <database name> –Confirm:$False
Mount Multiple Databases:
Furthermore, you can also use the following command if you have multiple Exchange databases to mount.
Get-MailboxDatabase –Server | Mount-Database –Confirm:$False
Step 6: Dismount the Exchange Database
You can also use the PowerShell cmdlet to dismount the Exchange Server database as described below (for the single database):
Dismount-Database –Identity <database name> –Confirm:$False
You can also use the PowerShell cmdlet to dismount multiple Exchange Server databases:
Dismount-Database –server <database name> –Confirm:$False
Conclusion
Mounting and Dismounting a database in Exchange 2019, 2016, 2013, and 2010 is not a complex task if performed by following the proper steps. However, there are chances of getting errors if the Exchange DB file is not in a healthy state. Thus, you should have a detailed knowledge of the entire process to make the job effortless.