Data Backup and Recovery

There are many reasons that data may be lost including user error such as accidental deletion or over-writing of data, data corruption, and physical disasters such as fire or flood. So to protect against data loss Information Strategy and Technology Services (ISTS) regularly backs up all of the University's centrally stored data.

NOTE: It is important to note that all information detailed in this topic relates only to centrally stored data, and does not apply to data stored on the desktop of your PC or laptop, on a USB, on an external hard-drive, or any other location outside of the University's data centres.

How often our data is backed up and how long the backup data is retained varies depending on the type of data or purpose of the data.  For the majority of data held in the University's data centres there are two backups performed.

Nightly Backups

As the name suggests, 'Nightly backups' are performed each night, and the data copied each evening is retained for 31 days.

End-of-Year Full Backup

The 'End-of-Year "Full" backup' is performed once a year, usually late in December or in January, and a copy of the yearly "Full" backup is retained for a minimum of 7 years; however some data is retained for a longer period due to legislative requirements (eg. Research data).

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.

Now 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.

The 'Shadow Copy' feature is now active on UniSA's network and share drive servers, allowing University staff to quickly and easily recover recent versions of files and folders without contacting the IT Help Desk or raising a service call.

If you are not able to recover the file or folder you require using Shadow Copy you can request the restoration of your data from a backup copy by contacting the IT Help Desk. It is important to remember that data backups are primarily for the purpose of recovering critical data in the event of a significant disaster; therefore all restore requests must be lodged immediately to ensure a successful recovery of data.

Further Assistance

If you require further information or assistance please contact the IT Help Desk on (08) 830 25000 or 1300 558 654.