If I specify the domain name in System->Administration->Network->General->Domain Name, this control panel seems to add the domain name after hostnames that you enter in System->Administration->Network->Hosts.
For example, adding the hostname tetsuo leads to this in /etc/hosts:
Then, when you try to do a "sudo -i", the sudo command fails, complaining that tetsuo (without the domain name) is unknown.
The only way to fix this seems to be to manually edit /etc/hosts and adding another alias like this:
192.168.x.x tetsuo.domain.name tetsuo
I'm wondering if the Network control panel can be fixed so it won't arbitrarily add the domain name to hostnames in /etc/hosts. It seems to do this everytime you save the network configuration, throwing away whatever manual edits you've made.