Backing up Exchange: Best practices for protection

For Microsoft Exchange backup, organizations must consider whether they back up Exchange Online, an on-premises Exchange Server deployment or a mixture of the two.

If an organization uses exclusively Exchange Online, the only real requirement is a current-generation backup product. Nearly all backup vendors offer Microsoft 365 backup capabilities.

For organizations that run Exchange Server on premises, Microsoft recommends using Exchange Native Data Protection as an alternative to traditional backups. However, only organizations that run Exchange 2016 or higher can use this option, and it requires a sizable Exchange Server deployment. Organizations with smaller Exchange Server deployments or older versions of Exchange should stick to a traditional backup.

When backing up Exchange Server on premises, use an Exchange-aware backup application. Exchange Server backups require the use of the Exchange VSS writer. Otherwise, backups will corrupt.

Check with your backup vendor as to how you should configure logging. Exchange Server uses transaction logs to store data that has not yet been backed up, so store transactions on a separate physical disk -- not just a separate volume -- from your database. The system uses transaction logs in the recovery process, so avoid the risk of storing them in the same place as the Exchange database.

It is easier to use a single product for backing up Exchange Server and Exchange Online than to try to protect the two environments individually.

Consider whether to use circular logging. Most backup vendors require you to disable circular logging if you plan to perform incremental backups, or if you need point-in-time recovery capabilities.

Finally, keep an eye on the free space available on the disks storing your Exchange Server databases. Backup products vary, but typically involve a lot of storage overhead in the restoration process. Ideally, the volume containing your Exchange databases should have enough free space to accommodate a second database copy, plus the extra space needed by the recovery process. Check with your backup vendor to find out the space requirement for backing up Exchange.

For organizations that use a combination of on-premises and cloud-based Exchange resources, it's best to find a backup vendor that supports backing up both environments. It is easier to use a single product for backing up Exchange Server and Exchange Online than to try to protect the two environments individually.