In General

What does the department back up for individual users?
Anything that is stored on the departmental filers is backed up to tape. This includes user home directories and web directories, as well as the /projects directories and software supported by the department. We also back up departmental servers, including, which contains some web directories. Home directories and project directories on the LECS network are also backed up.

Local partitions on individual machines are never backed up. Nothing of importance should ever be stored on a local partition, such as '/var/local', as it can disappear in the event of a disk failure, OS failure, or OS upgrade. Files placed in local storage will *never* be backed up by the department.

How long does the department keep backup tapes?
For the CS production network, tapes will be kept for one year. We will not be able to retrieve anything from backup that was deleted more than one year in the past. This is due to new security policies as well as changing technology and the instability of storing data on tape. The LECS backup tapes are also kept for one year only.

Does the department guarantee that files will be available for one year?
Unfortunately, tapes can deteriorate over time, and there is no guarantee that we will be able to restore files from them. The longer a file existed in a user's home directory, the greater the likelihood that we will be able to restore it, as it will be backed up on multiple tapes.

If a file was created after an archival backup run and deleted before the next one, there will be no instance of it on the archival tapes. If a restore request is made for such a file within a week, it might be able to be found on a daily backup tape, but this is not guaranteed to be the case.

Tape Backups

CS production network
The CS production filers and servers are backed up in full to archival tapes once per week. The archival tapes are kept for one year. Incremental backups are made daily on the servers only. The daily tapes are over-written after they become full and thus are not archived.

CS administration
The departmental machines used by staff are backed up to tape once per week. These machines include all staff Macs, as well as a few staff PCs running Windows.

LECS network
Home directories and project directories on the LECS network are backed up once per week. The tapes are recycled yearly. Nothing older than one year will be recoverable.

CSRES network
Users who have machines on the CSRES (research) network are responsible for their own backup. The department does not provide any backup for CSRES machines.

CD/DVD Backups
A page detailing CD or DVD burning is located here. If you are a faculty member and need some files burned to a CD or DVD but don't have a drive, please email udb@cs.

Laptop Backups
Laptop backup is available only for faculty-owned laptops. We will back up only the contents of the user's home directory (eg. C:\Documents and Settings\$USER on Windows and /Users/$USER on MacOS X) and there is a 10 gigabyte quota per user. The two most recent versions of any given file will be retained.

File Recovery

A series of hourly, nightly and weekly backups are stored in a directory called .snapshot in the top level of your home directory (CS production network). It will not show up in a listing of your directory, nor will it be tab-completed. The .snapshot directory is the first place to look after having lost a file that is needed. Files can be copied from a snapshot directory back into a home directory.

More information regarding snapshots can be found here.

Requesting restores from backup
Requests for file restores for files from the user's home or web directories should be emailed to Requests for file restores from administration Macs should be emailed to

In either case, the following information should be provided in the email:

  • When did you delete the file(s)?
  • When did you create the file(s)?
  • When did you last change the file(s), before the day you deleted it/them?

It can take a little while to find the file and do the restore, so please be patient.