Data back-up policy

Your personal directory (/massstorage/home/u123456) and team directories are automatically backed up on a regular basis on two tape libraries located in different sites, one at the SEGI (B26), and the other at the CHU (B35).

The back-up policy is defined as follows:

  1. Any file that has been modified and then left unchanged for at least 2h enters the backing-up queue and is backed up as soon as technically possible.

  2. The system keeps at most the 25 latest versions of each file for a maximum of 28 days.

  3. The last version of deleted files is kept on tape for 28 days.

Note

In the past, folders named nobackup were not backed up by the system. This is no longer true, so temporary data should never be written on the mass storage.

Attention

Since the tape system is only able to handle a limited amout of data per hour, any action impacting 1 TB of data or more (i.e., copying a large dataset or downloading large files), or a several thousands of files of less than 1 MB, must be reported before being performed to the UDI GIGA-MED so that these large operations do not affect the proper functioning of the back-up system.

Important considerations

This policy yields the following consequences:

  • newly created/modified files are backed up after 2h of inactivity, but the delay could be longer depending on the states of both the backing-up queue (e.g. if numerous files have been modified or if a large file is being backed up) and the back-up system. (i.e. if the system is momentarily down for maintenance).

  • versions of a file saved more than 28 days ago are automatically deleted from the system.

  • if a file is modified 12 times a day, the oldest recoverable version is only 2 days old.

  • no version of a file deleted more than 28 days ago can be retrieved.

Retrieving a previous version of a file

Warning

Due to the states the backing-up queue, the back-up system, and to the tools you use to work with your data, this procedure is not guaranteed.

To retrieve a previous version of one of your files, you have to contact the UDI GIGA-MED via SAM.