Frequently Asked Questions: Difference between revisions

The example above illustrates a frequent problem: <code>/project</code> for user <code>ymartin</code> contains too much data in files belonging to group <code>ymartin</code>. The data should instead be in files belonging to <code>def-zrichard</code>. To see the project groups you may use, run the following command:

* you have no <tt>setgid</tt> bit set on your Project folders.

 

If you already have data in your <code>/project</code> directory with the wrong group ownership, you can use the <code>find</code> command in conjunction with <code>readlink</code> to find and display those files:

  lfs find ~/projects/*/ -group $USER

If the output of <code>diskusage_report</code> indicates that a different group is over quota, use that group name instead of <code>$USER</code>.

Next, change group ownership from $USER to the project group, for example:

chown -R $USER:def-professor ~/projects/def-professor/$USER/

Then, set the <code>setgid</code> bit on all directories to ensure that newly files created will inherit the directory's group membership, for example:

chmod 2770 ~/projects/def-professor/

chmod 2700 ~/projects/def-professor/$USER

Each file in Linux belongs to a person and a group at the same time. By default, a file you create belongs to you, user '''username''', and your group, named the same '''username'''. That is it is owned by '''username:username'''. Your group is created at the same time your account was created and you are the only user in that group.  

The other two lines are set for groups '''username''' and '''def-professor''' in Project space. It is not important what users own the files in that space, but the group the files belong to determines the quota limit.  

You see, that files that are owned by '''username''' group (your default group) have very small limit in the project space, only 2MB, and you already have 34 GB of data that is owned by your group (your files). This is why you cannot write more data there. Because you are trying to place data there owned by a group that has very little allocation there.

The allocation for the group '''def-professor''', your professor's group, on the other hand does not use almost any space and has 1 TB limit. The files that can be put there should have '''username:def-professor''' ownership.  

Now, depending on how you copy you files, what software you use, that software either will respect the ownership of the directory and apply the correct group, or it may insist on retaining the ownership of the source data. In the latter case you will have a problem like you have now.

Most probably your original data belongs to '''username:username''', properly, upon moving it, it should belong to '''username:def-professor''', but you software probably insists on keeping the original ownership and this causes the problem.