Setting MX record


I have a newbie question.

I have installed e-mail server on my computer but it does not work because it can not connect to MTA. As I understood for that I need an MX record.

host -t mx has no MX record

host -t a has address XXX.XXX.XXX.XXX

My computer uses external DNS. For many reasons I can not request them to make me an MX record on it.

My question is

Can I set MX record on my computer without the need to install a DNS on it?

Thank you.

No, your DNS registrar has to add the MX record.

However a MX record is only needed if you want to receive incoming email on your server. Most people don’t, you get lots of attacks by spam bots etc. If you just want to relay mail to the outside, you don’t need a MX record.