Comment 71 for bug 32906

I happened to have my hostname a fqdn.
I changed the values of /etc/hosts around and ended up borking my sudo. I was mortified since it's a remote machine.
After trying a few things suggested here and elsewhere, I ended up changing the A record for my hostname to 127.0.1.1 and that got sudo working again.
Saved me a few hours of driving.
Cheers!