Error sender verify defer (making callout connection): T=remote_smtp Cannot assign requested address

[chronic]

Hi, for a few days I've been seeing this error in the /var/log/exim/paniclog log, frequently repeated:

sender verify defer (making callout connection): T=remote_smtp Cannot assign requested address

Can anyone tell me what could be the cause or where to start looking to understand what's happening?

I also have a specific customer who reported that messages sent internally on the same domain are randomly returned to him:

[email protected]
local delivery failed

421 Lost incoming connection
etc...

Could the two things be connected?

Thanks in advance to anyone who can help me

 

[zEitEr]

Hello,

Cannot assign requested address

Do you have a direct connection to Internet? Or is the server behind NAT? What DirectAdmin version do you use? And how many IPs do you hold on the server?

 

[chronic]

Hello,



Do you have a direct connection to Internet? Or is the server behind NAT? What DirectAdmin version do you use? And how many IPs do you hold on the server?

Yes a direct connection to the internet, not NAT.
It is a cloud server with Almalinux 8 that has been active for a few years now. The Directadmin version is the latest 1.675 (bcd6e3bf4a4dbfaeb423aae49ad2a0fd77206d7f) current channel, and all the other software is up to date, Exim 4.98.2, Dovecot 2.3.21.1, Spamassasin 4.0.1, and Clamav 1.0.8. I also use CSF firewall.
The server uses only one IP address.