UNIVERSITY OF CALIFORNIA OBSERVATORIES / LICK OBSERVATORY Network, Information, and Computing Services

Changing Unix File and Directory Permissions

1. Using an SSH Client such as F-Secure, open a connection to odin. Use the same login and password you'd use on bigdog or isis.
   
   
2. Move the directory containing your new directory. Most of odin's NT shares begin in /u/loen . deimos, dwg and dwg2 live there.

[Assuming that '%' is the prompt, type as follows:]
% cd /u/loen/dwg2
% cd hires
 
3. Confirm your location.

% pwd
Odin should return: /u/loen/dwg2/hires
 
4. List the permissions for your directory.

% ls -l HIRES-CCD <= or
% ls -l |more     <= shows all directories in hires
 

Sample output:
% drwxrwsr-x 5 loen DOS---- 512 Sep 5 15:10 HIRES-CCD
  ^ <= d for directory ('-' = file; 'l' = link)

% drwxrwsr-x 5 loen DOS---- 512 Sep 5 15:10 HIRES-CCD
   ^^^ <= user's (aka owner's) permissions (readable, writable,
executable/traversable)

% -rw-r--r-- 1 loen DOS---- 89088 Dec 31 1969 schedule.doc
      ^^^ <= group permissions (NT groups are readable, not writable, not
             executable)

% -rw-rw-r-- 1 loen DOS---- 89088 Dec 31 1969 schedule.doc
         ^^^ <= world (all) users' permissions
               (readable, not writable or executable)

NOTE: web pages must be world readable.
NOTE: world _writable_ is not recommended!
 

5. OK, so fix this, finally!
1. For files:

% chmod g+w schedule.doc <=add group write permissions
 
2. For directories:

% chmod g+wx HIRES-CCD <= add group write permissions
                         -- let any one in the electronics
                         or engineering NT groups view files
                         and change or add files.

NOTE: If you ever need to remove group write or read permissions, please let me know right away, so I don't accidentally clobber your changes!
 

3. Make your changes recursive (descend into directories, change all of their contents) 
   
   % chmod -R g+wx *
   
   

In our example, this command would make ALL directories in /u/loen/dwg2/hires group-writable.