Data Retention Duration

How long our backup data is retained varies, depending on the type of data or purpose of the data.  For example, Research data, Courseware (learnonline) data, and email data are all retained for different periods of time which differs to the retention of all other 'general' data.  For simplicity this topic details recovering 'general' data stored in the University's data centres.

As the nightly back-ups are retained for 31 days, we are able to restore lost data as at any point in that 31 day period.  This means that if a file was updated/changed several times over the previous 31 days we can restore the file as it was on any night in that 31 day period.
This is easiest explained by way of examples:

• If a file was accidentally deleted or corrupted three weeks ago, we can restore the file as it was the night prior to the accidental deletion or corruption.
• If a file was updated 10 days ago, and the updates made to the file were not valid or not required, we can restore the file as it was the night prior to the unwanted update.

This does not mean there are no limitations on restoring or recovering data within the past 31 days:

• If a file is created and then deleted on the same day it cannot be restored. As the file was deleted prior to the nightly backup being performed there is no copy of the file to restore.
• If a file is created and is then corrupted on the same day, only the corrupted version of the file will have been copied when the nightly backup is performed.

It should also be noted that copies of nightly backups of 'general' data are only retained for 31 days, so if the data to be restored is more than 31 days old it can only be restored as at the most recent End-of-Year "Full" backup, assuming the data existed when the yearly "Full" backup was performed.  If the data was created after the most recent "Full" backup, but is older than 31 days old, a backup copy of the data will no longer be available for restoration.