parsing mail.log. which emails failed? What does the stat field mean?

Question

I did a mailing and the program did not set the envelope adress correctly. So a lot of mails didng go through.

Now I am looking at the mail log and try to find out which mails I need to re-send.

The error codes seem to be somewhat ambigous so I looked at the stat= field.

I found out that the following different values occour:

Sent (-some-message-id Message accepted for delivery)

Sent

Queued

Deferred: 451 MAIL FROM: <www-data@ip-10-48-213-66.eu-west-1.compute.internal> Unable to verify MX-Record for domain ip-10-48-213-66.eu-west-1.compute.internal

Deferred: 450 4.1.8 <www-data@ip-10-48-213-66.eu-west-1.compute.internal>: Sender address rejected: Domain not found

Deferred: 421 invalid sender domain 'ip-10-48-213-66.eu-west-1.compute.internal' (misconfigured dns?)

Service unavailable

User Unkown

Data Format Error

Host unknown (Name server: some-server.com: host not found) 

Which do i need to parse out to know which emails didnt go through and need to be re sent?

Invalid sender domain sounds to me like a permanent error. But why is it "Deferred" then?

Answer 1

"Deferred" is a non-permanent error. Meaning the mail is not send yet. It will be retried later.

But as you can see in the detailed error message you have a very crippled DNS setup.