ping / nslookup / host not working
On a vBulletin forum that I use, the email notifications have been broken for some weeks. The tech guy has gone awol, and so I've volunteered to have a look. I'm not experienced in server administration, but I'm trusted by the site owners as I've been an admin to the forum before.
I would post up more details, but forum doesn't like URLs as I haven't made 15 posts yet.
ping domain_name returns unknown host.
nslookup domain_name returns can't find domain_name: No answer.
host domain_name has no output.
I'm thinking the problem must be related to this. Please help!
Thanks in advance.