Over the last few days I’ve received questions from several people inquiring if it is necessary and / or a best practice to perform a backup after a restoration of a database has occurred.
In general I do not think there is a best practice / guidance surrounding this question – in most cases the answer is it depends.
When I work a support case that necessitates the restoration of a database I will generally advise customers to perform a full backup once the database is in service and when the backup will not interfere with production hours.
For some customers the nature of the restoration makes this a higher priority – for example:
1) There were several days / hours of logs to play through (it would be nice to have a more current anchor point after recovery).
2) I had to resort to a hard repair of the database. (This process essentially invalidates all previous backups such that the next full backup would become the anchor point for future recovery).
3) Overall I’m not confident the issue that caused the need for restoration was actually addressed (it would be nice to have a more current point of recovery in anticipation that we’ll be doing it again soon).
There are also another set of customers where capturing a full backup is advised – those customers that are using an incremental backup strategy. After a database is restored the previous full backup information is cleared from the header of the database – this would indicate that further incremental backups will fail with an error message that a full backup needs to be performed. Therefore, customers that use a full / incremental backup strategy it would be advisable to perform a full backup prior to the next scheduled incremental so that backup job failures do not result.
(You can do the get-mailboxdatabase –status command to see the times of the last previous full and last previous incremental backups).
I think it goes without saying – you really cannot go wrong with ensuring that you have a current backup after any type of recovery operation.