Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

When I try to switch to another user from the command line using "su", I get an authentication failure, as shown below:

su - otheruser

Password: *****

su: Authentication failure

Yet I know that the password is correct because I can successfully log in to the desk top as the other user from the Ubuntu login screen.

Does anyone know what could be causing this problem?

share|improve this question

See this page for what you should use for a rootshell: RootSudo

This page also will explain how to get a terminal as another user. Short version: sudo -i -u <username>

There's an Ubuntu SO-based site here: http://askubuntu.com/

share|improve this answer

You need to be root to do "su". You can "sudo su - user" or you can "sudo su -" then do "su - user". Enter the password of the user you are now when you do the sudo. ex. "whoami"

share|improve this answer
    
Don't use su on Ubuntu. – Broam Oct 13 '10 at 17:59
    
My question is why is it there if I should not use it? Ok, how about this one: "sudo -u <username> <command>" ? – SuperJames Oct 14 '10 at 13:46
    
Please see my answer for why - the official justification is listed there. – Broam Oct 14 '10 at 19:19
1  
sudo -i is proper if you need a rootshell. See ubuntuforums.org/showpost.php?p=6188826&postcount=4 – Broam Oct 14 '10 at 19:22

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .