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.

postfix is sending mail to the last preference mx record (ie:50 instead of 5)

Biggest problem is the domain its sending to, the last mx record is dead so the server doesn't respond.

I've tried to do a smtp test on the first few mx records and they accept connections.

How can I troubleshoot why its going to the last record, and how can i resolve (if its just skipping the rest and not because connections are refused)?

share|improve this question
    
Do you see any useful information in your postfix logs? –  larsks Jan 20 '11 at 18:01
add comment

1 Answer 1

Postfix is RFC compliant and tries the MX with highest priority (lowest value) first. With one exception: caching. If Postfix encounters a problem (defer, reject) on the first MX it tries to deliver to the others. The first successful MX will be cached for a few hours (I think it was 24 hours), unless the cached MX will also fail.

So if postfix shows your symptoms it is mainly a DNS setup error or based on the caching "problem".

You can see the answer of the Postfix author to a similar question here.

share|improve this answer
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.