We run AFS practicaly for all services, including home directories, web pages, sorftware distribution, mail serving, etc.

AFS is a widely used networked filesystem more secure and reliable than many of its alternatives, hence it requires the user to know some basics about its functioning. This page provides the introduction information, for the user manual address to Fysikum AFT User Guide

Accessing AFS

Some "complications" which AFS needs in order to provide protection against hackers and let you access the home directory from all computers:

  • It is your responsibility that you have an AFS ticket when you or your programs needs to access your home directory!
  • AFS handles the file access rights differently compared to "ordinary" Unix.

AFS tickets

To access your files in AFS you need an AFS ticket. You get one automatically if you log on to an AFS computer, and you can renew that one by issuing the "aklog" command. Tickets have limited lifetime (typically 24 hours), and thus you must renew your ticket now and then.

If you have a program running and your ticket expires, the program will be denied files access, which probably will break the run. Thus: DO NOT FORGET TO RENEW YOUR AFS TICKET!

AFS file permissions

AFS has an own system of file permissions. The command 'chmod' can be used to set file permissions as in "ordinary Unix"; but now only the "owner"-part of the permissions are used, and they apply to everyone that are allowed to read the file due to their AFS-rights.

      You check and modify the AFS rights with the 'fs' command.

  • To check what rights is set for the directory 'test' do:
    fs la test


  • To give user 'walck' the right to read and list files in your test directory:
    fs sa test walck rl


  • To remove all rights for walck in test:
    fs sa test walck none


  • To get more help about what you can do with fs:
    fs help