su Command Returns "Authentication Failure" ??? SOLVED

[mhumm2]

The subject line describes the situation exactly.

mark@mark-AMD:~$ su
Password:
su: Authentication failure
mark@mark-AMD:~$

I don't understand why I can't switch to super user mode. The password is good since it's the same as the one I log in with.

Any advice would be appreciated.

mhumm2

[Fintan]

Re: su Command Returns "Authentication Failure"

This may be of help:
Special notes on sudo and shells
Quote from here:
https://help.ubuntu.com/community/RootSudo

None of the methods below are suggested or supported by the designers of Ubuntu.

Please do not suggest this to others unless you personally are available 24/7 to support the user if they have issues as a result of running a shell as root.

To start a root shell (i.e. a command window where you can run root commands), starting root's environment and login scripts, use:

sudo -i (similar to sudo su - , gives you roots environment configuration)

To start a root shell, but keep the current shell's environment, use:

sudo -s (similar to sudo su)

For a brief overview of some of the differences between su, su -, and sudo -{i,s} see :
http://ubuntuforums.org/showpost.php...26&postcount=4 .

For a detailed description of the differences see man su and man sudo .

Read carefully
Hope this helps

[mhumm2]

Re: su Command Returns "Authentication Failure" SOLVED

That did it. The only thing I don't understand is that su worked at one time and now it does not. I'm good though because sudo -i and sudo -s both work as advertised. Thanks Fintan.

mhumm2

[Fintan]

Re: su Command Returns "Authentication Failure" SOLVED

Glad to be of help