i am running linux ubuntu mail server, over the weekend emails stop coming in or going out. i dig my server from the server itself and i am get this results

perfectpol@mycompany$ dig mycompany.com mx
;; global options: printcmd
;; connection timeout; no server could be reached

then on a window workstation the results of nslookup is
server: www.mycompany.com
address: 179.a.a.6
***www.mycompany.com can't find mx: Non-existent domain

contact my ISP and said the problem lays with local, since my server does host the emails. (by locally mean host them at my company server)

I supectthat mx files have been corrupted or delete. How then should i resolve this, firstly I am new to the company and not all that good in linux. All the server is in command line. I tried to view the /etc/resolv.conf and it was blank. HELP.

thanks

you would need to edit the nameserver zone files.

you would need a record such as

assuming dns is the problem here
if possible, could you find out which type of dns server is running and if you even host it...

you need to do a bit of verbose checking here....the hosts connecting to the mail server - what is their error message?

First there are no such things as mx files There are mx records which are a component of the dns system and specified inside the configuration file for the domain.

From what you're saying you host your domain on bind? If so post your bind configuration files and we'll give you a hand getting things in order.

As far as your /etc/resolv.conf goes it should probably be:

search mycompany.com
domain mycompany.com
nameserver IPAddrOfNameServerPrimary
nameserver IPAddrOfNameServerBackup

You can view a file by 'cat'ing it... eg: cat /etc/resolv.conf and you can edit a file in vi, nano, pico, etc.