Weird errors: Can't send mail or ping hosts

[Celion]

Hey everyone!

I'm having some weird issues on a machine. The machine has been running for a year or so without any problems. But since yesterday we are unable to send any mail to any host. Also we are unable to ping any domainnames, they wont resolve. Though ip's are pingable without any problem.

In the exim log we find errors like:

rejected RCPT
host lookup did not complete

What should i try/check to downsize the cause of this problem?

If you need any information to answer my questions, please ask and i'll provide it asap.

Kind regards,

Patrick

 

[chatwizrd]

Make sure the nameservers listed in /etc/resolv.conf are working.

 

[Celion]

as far as i can tell they are

 

[nobaloney]

Then try nslookup on the domains that you get the error for that host lookup doesn't complete.

That error specificallly means that the nameservers listed in /etc/resolv.conf can't find the domain.

Jeff