MX record confusion

Hello. I currently run a mail server at my office. We only have one ip address from our isp. That connects to our router and all of the clients plug into it.

Now, i also have my mail server connected to the router as well.

What do i need to do to configure this to work correctly? I know i need an mx record pointing to my ip address, but what should it be called? mail.domain.com? Or just domain.com?? And if i do name it mail.mattrk.com, should the hostname on my mail box be set to something? I'm a little confused on the whole issue. Basically, i can get email now (without an mx record) but i cant send becasue everyone does reverse look ups and the connections always time out. Thanks for the help!!

-Matt

In terms of anit-spam rules in mail servers...

Most servers simply look for the existence of an MX record. So, it doesn't matter. It's common for your mail server to be "mail.yourdomain.com" but it can be anything. In your zone, I recommend:

@ IN MX 10 mail.yourdomain.com.
mail IN A 1.2.3.4

Notice the trailing dot on the MX record!
-c

I think you should also have a PTR record for that IP put into the reverse dns zone file. Kinda new to this myself, but I was having an issue with our email because spam filters would deny our email since they could not do a reverse dns lookup..so make sure that's taken care of as well. Peace and good luck.

g33k0 is right you need tp have a PTR (pointer) record setup for the reverse lookup.

*Now, i also have my mail server connected to the router as well.*

This means you will need to configure your router to forward anything coming in on port 25 to your mail server.

That's redundant because nobody on earth will query it for answer.
You may be the registrant for your domain and host it yourself, thus you can control what IP your domain points to.
For your IP your ISP is likely the registrant, unless you lease a huge block, then there is a little chance they can delegate that to you. That said, no matter what PTR record you set, nobody on earth will query it.
If you are talking about an internal network then the IP, say 192.168.0.1, can be under your control and set it up with a PTR record.