Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

Our systems cannot send e-mail to a company that has no MX record. There is an SMTP server running on their IP address and they are able to get e-mail from gmail. Is it normal for mail systems to try to connect to a SMTP server at the A record when there is no MX?

share|improve this question
add comment

2 Answers

up vote 10 down vote accepted

Yes it is standard, per RFC 5321. Please see the Wikipedia page on MX Records

share|improve this answer
1  
and it has been standard ever since RFC 821 too. This also means that if you don't have MX records and insist on having a website without the 'www' prefix then that server will get inbound SMTP attempts too :( –  Alnitak Jan 27 '10 at 0:53
add comment

Normally yes, if no MX record exists, the A record should be used as a failsafe.

share|improve this answer
6  
It's not a "failsafe". Originally mail was delivered to hosts (via A records) and then MX records were invented to say "actually, send it somewhere else instead...". –  Alnitak Jan 27 '10 at 0:54
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.