Arch Linux

Capt_Wilard

Member

Registered: 2021-07-10

Posts: 3

su - Authentication failure in terminal and installing in GUI

Hi

I wouldn't be here unless I was really stuck.

I have come so far in installing ARCH but I can not understand where I have gone wrong, so I hope you can help.

I am the only user of my PC. I can ‘sudo’ in the terminal and install as normal.

My user name is in the ‘sudoers’ group, but I can not, ‘su’ in the terminal without getting an Authentication failure.

Moreover, when I try for example to install/search for a scanner and I need
Administration password to install it. I get an Authentication failure in the dialogue box!!

I have tried various posts, some outdated but still helpful, so if you can direct me to the right place
or if you have any solution, then I thank you in advance.

Administration password I agin get an Authentication failure in the dialogue box

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,501

Website

Re: su - Authentication failure in terminal and installing in GUI

My user name is in the ‘sudoers’ group

And have you modified the sudoers file so that a "sudoers" group means anything at all?  By default it doesn't.

but I can not, ‘su’ in the terminal without getting an Authentication failure.

sudo and it's configuration (and group memeberships) have absolutely nothing to do with su.  Are you having troubles with sudo, or with su, or both?  Please post your actual commands and output

I get an Authentication failure in the dialogue box!!

Ah ... what?  What dialog box?

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"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman

Capt_Wilard

Member

Registered: 2021-07-10

Posts: 3

Re: su - Authentication failure in terminal and installing in GUI

Thank @Trilby for your reply.

What I mean by dialogue box is when I am for example in the Gnome DE, and I want to install the scanner..
I go to the document scanner prog and it then searches for the scanner, and then
a box appears saying Authentication Required; I put in my password and it then fails with a authentication error.

As for the sudoers file I have thus far uncommented in /etc/sudoers

%wheel ALL=(ALL) ALL
%sudo ALL=(ALL) ALL

using EDITOR=nano visudo

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,501

Website

Re: su - Authentication failure in terminal and installing in GUI

... a box appears saying Authentication Required; I put in my password and it then fails with a authentication error.

I have no idea what program that would be, or whether it would even be wise to give it any password, but it's surely asking for the root user password, not your user's password.  This would be the same for `su` in the terminal.  I suspect you are trying to use your user password for `su`; that is not supposed to work.  You need to use the root password.

Last edited by Trilby (2021-07-10 14:58:38)

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"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman