EDB or Exchange database files store all the mailbox data, which ultimately grows big when new users and data are added. This can have an adverse effect on business performance and introduce Exchange Server errors that might be unavoidable.
Before we learn about how to deal with EDB file too large issue, let us focus on the consequences of large size EDB files.
- When Windows EDB file size is too large, the chances of data corruption are high.
- Large size of EDB file can cause database dismounting issue.
- Slow down the performance of database operations.
- Makes managing mailbox data a difficult task.
- Cause issues in database recovery and backup.
It is important to manage the database and troubleshoot such problems within time to avoid issues to keep the database healthy. Let us discuss the consequences of Windows EDB too large in detail.
What happens when you don’t reduce EDB file size?
An Exchange Database contains multiple user mailboxes, and there can be multiple databases in a single Exchange Server. As the size of the EDB grows, it becomes a hassle to manage Exchange EDB file size. Below are some drawbacks/ repercussions of an EDB file too large in size:
Abrupt database dismount
When the EDB file size keeps on increasing and fills the database to 100% of its capacity, the Information Store service will dismount the .edb file. It will affect the whole organization, as all email-related work will be halted until you reduce EDB file size in Exchange Server.
Slow search
It is difficult to search the mailbox items in a large EDB file. Indexing all the mailbox items in an oversized database requires heavy resource usage. This, in turn, leads to slow indexing and searching. Things become worse when your EDB file has duplicate data. It further slows the whole search process and often lowers productivity.
Corruption in database
I have seen it happen multiple times. When the EDB file size is too large, the database crashes several times. Multiple sudden crashes lead to EDB file corruption. To resume the state of the work, admins need to immediately repair corrupt Exchange database either by replaying the uncommitted logs or with an EDB backup file.
Why admins suggest reducing the Exchange EDB file?
When you reduce EDB file size, it not only makes space for more emails but also brings more benefits to the Exchange Server.
- The response time of the Exchange Server increases for the mailbox request, and the email communication becomes faster.
- The white space in the EDB file is reduced, making room for new email and other information.
- Mailbox management becomes easy when you periodically manage Exchange EDB file size.
Best practices for Exchange Server Administrators to reduce EDB file size
If the administrators follow the below practices, avoiding EDB file issues is very easy.
- Execute Exchange Best Practice Analyzer: Microsoft provides an application called Exchange Best Practices Analyzer that the administrator must use to get an overall picture of the Exchange Server condition and configuration. The tool will retrieve the information related to the Active Directory, registry settings, performance metrics, etc. The administrator will get a clear understanding of how Exchange Server is using its resources and the steps to reduce EDB file size in Exchange Server.
- Review the SMTP logs and queues: The SMTP logs and queues contain the information related to the communications through the Exchange Server. If the administrator checks these logs and queues, then it can clear many aspects related to the causes behind message failures. When the messages are stuck in the queues and not processing, these logs and queues can help the administrator.
- Check anti-virus and anti-malware software updates: There are professional anti-virus and anti-malware software available that support the Exchange Server and protect its environment. Sometimes, this software requires a manual update, and the administrators do not run on time; then the software may not provide more security to the Exchange Server. If the administrator updates the anti-virus regularly, then it can help improve the performance of the Exchange Server.
How to reduce Exchange EDB file size?
Exchange administrators may not realize the growth of their Exchange databases. And this unusual growth often leads to database dismounting and inaccessibility issues. Luckily, there are many ways to reduce EDB file size in Exchange Server. Some are discussed here:
Delete unwanted data from the database
It is one of the most obvious methods to effectively manage Exchange EDB file size. Deleting unwanted data will create more free space for adding new data. But make sure you don’t end up erasing important data accidentally, which is why it is important to backup the whole Exchange database before you make the move. However, it may happen that even after deletion, you do not see any reduction in the size of the EDB file. But don’t worry—the space cleared by deleting the data is there and Exchange will use it whenever users are adding new data (instead of increasing the database size).
Perform offline defragmentation or move data to a new database
Offline defragmentation helps remove white space in the Exchange database, allowing you to reclaim the free space available. This process compresses databases, erase the blank and unused space, and reduces the database size. Thus, it effectively brings continuity in storage. Eseutil is the Microsoft utility that helps in defragmentation, and you can use the Eseutil switches to defragment and repair EDB files. However, this process has its disadvantages, making it a slow process and can be performed only after dismounting the database (it means that all the mailboxes of the database will be unavailable for a considerable period of time). Once the process is completed, you need to mount the database again to restore the Exchange Server.
Performing defragmentation using Eseutil
You can get the amount of whitespace in a database by running the following cmdlets in Exchange Management Shell:
Get-MailboxDatabase -Status | Format-List Name, DatabaseSize, AvailableNewMailboxSpace –Auto
Before starting defragmentation, ensure that you have enough free space (110% of the size of the database) available on the server (or the network). Now, stop the Exchange Information Store service, and follow the procedure below to perform the defragmentation:
- In the Exchange Management Shell, navigate to the location of the database file.
- Dismount the Exchange database for which the defragmentation is to be done:
Dismount –Database <Database Name>
- Perform defragmentation by running:
Eseutil /d "<database location\DatabaseName.edb>" /t "<a temporary location\TempDatabaseName.edb>"
- Mount the database again
Mount –Database <Database Name>
- After the completion of the defragmentation process, start the Information Store service.
- Check if the database has been mounted, and then verify if the emailing is working.
- Finally, check the white space to verify the success of the defragmentation.
Remember: The speed of Eseutil utility is usually 9 GB/hour and may vary according to the hardware and system environment.
Move mailboxes to new database and delete the old one
Instead of performing defragmentation, many Exchange administrators create a new database, and then move Exchange mailboxes to new database from the older one. The older one can be deleted thereafter. It helps them achieve the same results as defragmentation. The advantage is that the mailbox downtime is negligible. Also, it can be done from the Exchange interface (like Exchange Admin Center).
Back up the data and delete it from the server
Exchange administrators can back up the unused data in a different location and delete the same from the server to reduce the database size. And for exporting, they can try ExMerge or export cmdlets, depending on the version of Exchange.
In Exchange 2010, use the following cmdlets to export mailboxes to a PST file:
New-MailboxExportRequest -Mailbox <Mailbox Name> -FilePath < network share path of PST file >
You can also use the EAC to export mailboxes. But if your EDB file is dismounted, then you cannot use either EAC or the EMS to export mailboxes. In such case, you have to utilize a specialized EDB to PST converter tool that allows you to access the offline .edb file and export bulk mailboxes to PST.
Conclusion
As an Exchange admin, you must make sure the server is always at its peak performance. Remember to create a comprehensive EDB file backup before you try the above methods to reduce EDB file size in Exchange Server. In such a case your EDB is corrupted due to the oversized EDB file, repair it with eseutil (soft or hard recovery), and if that fails (due to severe corruption), use an advanced Exchange database recovery tool.
