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Backup and recovery
19 Dell EMC SC Series: Microsoft Exchange Server Best Practices | CML1037
5 Backup and recovery
5.1 Backups and snapshots
5.1.1 Backup schedules
A standard backup schedule should be established for every Exchange environment. This backup schedule
should include at least one full backup per week. If an environment is small, or if time permits, a daily full
backup is optimal.
With Exchange 2013/2016/2019, Microsoft recommends using database copies to eliminate regular backups.
By having at least three copies of each mailbox database, Microsoft considers these to be highly available. In
addition, Microsoft recommends having several lag copies of each database available in case there is a need
for a point-in-time copy (logical corruption).
5.1.2 Snapshots
SC Series snapshots (Replays) with Replay Manager are recommended for use with Microsoft servers.
Snapshots make an easy means to recover individual mailboxes or entire databases very quickly. However,
they are not intended to replace regular backup processes because some verticals have specific regulatory
requirements relating to data retention.
Business requirements will dictate the backup schedules to be utilized. As a rule of thumb, Exchange VSS
snapshots using Replay Manager services for Microsoft servers can be taken in 15-minute increments.
Beyond that, the options are limitless concerning the flexibility of snapshot schedules. It is important to note
that if the database consistency check will run with the backup set, it may not be possible to complete the
snapshot and consistency check before the next scheduled job runs when scheduling around the 15-minute
window.
By design, VSS data has to be captured within 10 seconds or the snapshot will fail. Since Exchange
2013/2016 allows databases and logs to reside on the same volume, there are fewer volumes that need to be
part of a backup set. Is it recommended to include no more than 12 mailbox databases per VSS backup set.
This will allow the snapshot to complete within the 10-second window.
5.1.3 Database verification
To run the database verification process as required by Microsoft, Replay Manager for Microsoft Exchange
Server provides a verification service that can be used to mount the database snapshot after a successful
snapshot to a utility server. The database verification process is a time-, processor-, and memory-intensive
operation. It is a critical part of the backup process, but due to the amount of time that it can take, customers
who do frequent database snapshots will typically only run verification on the database(s) once a day to check
for consistency.