| Sender domain resolution problems [message #145245] |
Mon, 11 March 2019 18:10 |
j.a.duke
Messages: 239
Registered: October 2006
|
|
|
|
I'm seeing the following two errors in my Security log (often with different IPs):
[07/Mar/2019 13:00:01] Message from IP address 207.211.31.81, sender <sender<_at_>example.com> temporarily rejected: sender domain does not resolve
[07/Mar/2019 19:09:36] Client with IP address 205.139.110.120 has no reverse DNS entry, connection rejected before SMTP greeting
I've done lookups on both of the addresses and they resolve back to mimecast.com outbound SMTP servers. In fact, all the Mimecast servers generate both of these errors, but it isn't 100% reproducible. So each server doesn't always fail a reverse DNS lookup.
Is there a place that I can have Connect bypass the lookup for their IPs and accept the message? I'm not finding it. I've entered the Mimecast IPs into my "Trustworthy" group, which is excluded from Blacklists, Caller ID, SPF, Greylisting & Spam Repellent.
Is there someplace else I should exclude them or otherwise allow the messages to be accepted?
Thanks.
Cheers,
Jon
Updated to fix typos courtesy of auto-correct.
[Updated on: Mon, 11 March 2019 19:17] Report message to a moderator |
|
|
|
Members
Search
Help
Register
Login
Home
