KDE su stopped working

[massu]

So, rather unexpectedly after I got Kubuntu up and running, I tried to open up Wireless Assistant in KDE and got a "Su returned with an error" message. I've been checking through topics on here, but everything seems about as clear as mud thus far.

I've tried running sudo and kdesu from the console to see if I could run kcontrol from there, and here's what I got:

smatthew@:~$ sudo apt-get update
sudo: unable to lookup via gethostbyname()
matthew@:~$ sudo apt-get update
sudo: unable to lookup via gethostbyname()
matthew@:~$ sudo passwd root
sudo: unable to lookup via gethostbyname()
matthew@:~$ sudo kcontrol
sudo: unable to lookup via gethostbyname()
matthew@:~$ kdesu kcontrol
X Error: BadDevice, invalid or uninitialized input device 168
 Major opcode: 145
 Minor opcode: 3
 Resource id: 0x0
Failed to open device
X Error: BadDevice, invalid or uninitialized input device 168
 Major opcode: 145
 Minor opcode: 3
 Resource id: 0x0
Failed to open device
xauth: (argv):1: bad display name ":0.0" in "list" command
kdesu (kdelibs): WARNING: No X authentication info set for display :0.0
matthew@:~$

I seem to be having at least two different problems here, with the gethostbyname() problem probably being the reason I can't use kdesu or sudo to get admin access to anything.

Everything was working fine before, and I have no idea why everything would suddenly not work. Anyone have any idea as to what's going on here?

[javierrivera]

Re: KDE su stopped working

It's most likely cause is that the computer has no name (empty /etc/hostname), or it is unable to resolve it (problems in /etc/resolv.conf).

You can find some info here:

http://ubuntuforums.org/showthread.php?t=78324

Javier.

[massu]

Re: KDE su stopped working

Well, I seem to have myself in an interesting situation. hostname returns that my hostname is (none). However, /etc/hosts gives "Shinji" (without the quotes, of course) as synonymous with "localhost", looking something like this:

127.0.0.1 localhost.localdomain localhost Shinji

/etc/resolv.conf is set the same way (I can't post the exact contents of it right now, as I don't have internet access at the moment in Kubuntu without plugging my laptop directly into my router, which I can't get to at the moment.) with my hostname being Shinji.

Now, when I try to use hostname to set my hostname, it tells me that I can't do so without being root. And, of course, I can't do any admin tasks at the moment anywhere in the system because of su/sudo/kdesu being broken! I seem to have found myself in a circular situation, here... suggestions?

[penguin.ch]

Re: KDE su stopped working

I seem to have found myself in a circular situation, here... suggestions?

You may break the "vicious circle" by means of a live system (as described in analogy on this page) ... 8)

--

Postscript: reference updated

[javierrivera]

Re: KDE su stopped working

Or just reboot in safe mode, as advised on that thread .

Javier.

[massu]

Re: KDE su stopped working

I managed to get into my hard drive from the live CD... it turns out that my /etc/hostname was completely empty (!), so I ran Kate as superuser and edited that to add "Shinji" as my hostname. I then logged back onto my Kubuntu setup on my harddrive and, voila, everything works again!

I actually think I know what I did... I think I cleared the hostname entry on the network settings tab. I don't know why, but that seems to be what I did. Oh well. I live and I learn.