sudo broke on my laptop after upgrading to kubuntu 8.04 - aargh!

sudo: unable to resolve host treacle
sendmail: fatal: open /etc/postfix/main.cf: No such file or directory
[sudo] password for dcminter:

I don't know why it stopped being able to resolve the host name specified in /etc/hostname, I don't know why it was ignoring my password, and I really don't know why sudo started producing an error message for sendmail. Very odd.

This initially seemed to produce a bit of a bootstrap problem - I needed to be root to fix the problem, but how to get to root? Fortunately it turns out that the kdesudo program was still working just fine:

kdesudo -c xterm

That prompts you for a password and then provides an xterm logged in as root. Very handy. I added the following line (my laptop's hostname is treacle) to the /etc/hosts file:

127.0.0.1        treacle

It seems happy enough now. So far nothing else is conspicuously broken. Now that I finally can, I just have to disable the ghastly system beep again (it's hard to understate how much I hate it). To do that, add the following line to the /etc/modprobe.d/blacklist file:

blacklist pcspkr