Dearie > Sent: Tuesday, March 01, 2022 at 5:47 AM > From: "Bob McGowan" <[email protected]> > To: [email protected] > Subject: Re: Authentication failed after su- > > On 2/28/22 13:09, Dan Ritter wrote: > > sudo su - -l -c "rest of the line" > > Some comments on this, without knowing just how it failed: > > 1. There is no reason I can see to using both 'sudo' and 'su' > together. By default, they both let you run a command as the root user. > Thanks for the clarification.
> 2. Using both '-' and '-l' with su is redundant, they do almost (per > the man page) the same thing. The man page suggests '-l' is better due > to reduced side effects. > I wonder what "side effects" they may be. > 3. The -c option provides a means to tell su to run a specific > command. So the string 'rest of the line' generates an error stating > 'command not found' if run as is. You need to supply this part of the > line so processing can be duplicated and evaluated. > Thanks once again. > If I insert an 'echo' before the word 'rest', there is no error. > Noted. > Hence, the actual error is needed, as well as the actual command being run. > The actual command is actually lifted from Debian Wiki (https://wiki.debian.org/WiFi/HowToUse). It is: su -l -c "wpa_passphrase myssid my_very_secret_passphrase > /etc/wpa_supplicant/wpa_supplicant.conf" In a terminal, I typed: username@hostname:~$ su -l -c "wpa_passphrase JupiterRising 1234567890 > /etc/wpa_supplicant/wpa_supplicant.conf" Password: su: Authentication failure username@hostname:~$ The error message is Authentication failure. Please note that I have chosen not to create a root password during the process of installing Debian 11. Best regards. Stella
