Postfix Incoming mails from external domains not working

Support
1

Yunohost/Postfix emails works locally and sending to external domains also works but incoming from external domains is not working.

Netstat shows SYN_RECV from external domains trying to deliver but nothing more happens.

Proto Local Address Foreign Address State
tcp mydomain.com:smtp loninmrp22.uk.db.:19608 SYN_RECV

/var/log/mail.log don’t show up errors or any reference to incoming attempts.

DNS settings I use are

A myhost.mydomain.com 111:222:333:444
MX myhost.mydomain.com
TXT @.mydomain.com “v=spf1 mx -all”

Router port forward is properly set. It seems ISP is not blocking any ports. Online port scan tells me that port 25 is open.

However netcat when ran locally returns “Service ready” but from outside (another computer with different ISP) returns no response.

nc 111:222:333:444 25
220 mydomain.com Service ready

I am using Yunohost fresh install with default configurations.
I am running out of ideas any help would be highly aprreciated

2

It’s strange!

Check your firewall rules.

For me if the service is ready inside your local network, it’s your router that don’t redirect 25 port.
Try to establish a connection with netstat or openssl to your yunohost .
Verify that inside your yunohost you can ping domain name exemple:
ping wikipedia.org

May be your email are grey listed, you should wait 30 minutes, to be sure.