Policy

Introduction

This is the draft version of the policy for the use and backup of the T2 Belgium user disks located at the computing center in the ULB.
Please note that this is a work document and as such is intended to be discussed. However, once agreed upon, we think that this policy should be respected as much as possible (we are aware that they are probably a lot of exceptions, but these we would like to evaluate case by case).

User space

The user space will be found at /home/username (where username is your username :-) ). Quota will be set for each user on this disk. The default quotum will be 150Gb. This should be more than enough for a typical user. This also means that large files should not be copied to the user space, but should be left on the pnfs file system. By large files, we mean everything over 10 to 20GB
However, as the quorum is set per disk partition, users producing data for the a group of users might come in trouble. Therefore we propose to have a dedicated user set up (for instance a user 'top' that has a higher limit.

msa disks

Up to now people were using the msa and beo disks for storage. These disks will still be accessible from the T2, but their use is not recommended any more.
These disks will be mounted as external drives, but the access will probably be slow.

Backup

Backup scheme

The backup will be done via the creation of a zipped tar file. This has the advantage that roughly 6Gb of code can be compressed to 2Gb.
For the daily backup, the option was taken to have a full backup on Sunday of all the files, and an incremental one the rest of the week. At this moment, it is impossible to backup the full user disks. Therefore, per user 2 Gb of compressed data will be backed up.
Additionally, weekly and monthly backups will be guaranteed.

Procedure

Each user will have the possibility to define his own backup scheme. To this end he will:

• Create a directory .Backup (the dot is important, as is the capital B)
• In this directory, make a file daily, weekly and monthly, for the respective backups
  • each line of this file gives instructions for the backup
  • directory names will be backed up recursively
  • if the directory is precede by a -, it will not be backed up, nor its sub-directories
  • a line starting with - and ending with * will be interpreted as pattern: example:
  • -tmp* will not back up anything that matches *tmp*