Disk Quotas at PCN

Users of PCN Unix systems do have quotas for their home directories. The disk quota is a limit to how much you can store in your home directory. This ensures that we have sufficient storage for everyone in the building.

• Physics Faculty have a 2 GB quota
• Physics Staff/Students have a 600 MB quota

If you suspect that you might be running up close to your quota or you are receiving a quota error while trying to login to a UNIX workstation, you can check it with the quota command:

% quota
Disk quotas for user foobart (uid 999999): 
     Filesystem  blocks   quota   limit   grace   files   quota   limit   grace
/net/aristotle/home
                  12920   500000  600000            105    6000    7500

Your quota is the field labeled 'quota'. If you reach this point, you can still write up until you reach the hard limit ('limit'). Once you reach the 'quota' limit, you may have issues logging into the graphical interface of a UNIX workstation.

Use the following tips to get back under the quota.

• Check for problem directories to see what is eating up all the space:

  cd ~
  du --max-depth=1 -h
   
  #NOTE: Use the following syntax if you are logged into Bohr
  cd ~
  du -d 1 -h

  Using that command, you can see the total size of each directory in your home directory. Use that information to prune your directory tree.

• Check to see if you have /project space available. If you do not specifically know of any you may contact your advisor or check with someone else in your group.
  
  If any exist, you can redirect certain items to those locations.
  

  man ln
  ln -s <source-dir-or-file> <destination-link-name>

  Use the first command to get more information about the ln command. The second is a basic structure to symbolicly link to a file/folder contained on a different part of the filesystem.

• If you have unimportant data cluttering up your /home directory, a number of systems have /scratch space available. This /scratch directory is NOT BACKED UP AT ALL, EVER!