Zimbra as a smtp relay for a domain
First I would like to apologize if this is not the correct section. I am a newbie in Zimbra. Here is what I am looking for:
I have a domain let say test.com. I have installed Zimbra server in the local office. The Zimbra is NATed to an external IP with hostname mail.test.com. I want to authenticate my domain with zimbra server, in other words to use zimbra as a SMTP relay, but to be open only for incomming mails from test.com.
First I know that I have to add MX record for host - mail.test.com in the DNS where is the domain. I want to use it only for relayed e-mails from test.com
The other strange thing I noticed is that I have tested server on its IP. Telnet to port 25 is ok, but when try to send mail via console all the mails are "Relay access denied" ?
This is my first mail server installation and I am sorry if the questions are stupid.
Any help is highly appreciated.
Thanks in advance