Relay not allowed for receiving mails

[Kidswiss]

Hi

I'm trying to replace my old postfix/dovecot based setup with stalwart.

I have a stalwart instance on a VPS with static IP and reverse DNS for sending mails. It's just configured with one single account and it's job is to act as an relay for the on-prem mailserver with dynamic IP.

The MX record point to the on-prem mail server, with postfix it's been working for years. The on-prem mailserver is behind NAT, so all I do on that end is changing the port forwarding to switch between postfix and stalwart.

The on-prem mailserver is configured to use the one on the VPS as a relay, and I'm able to send mails to gmail with no issues.

However, the problems start with receiving mails from gmail. If I try to send an email from gmail to my server I will get:

550 5.1.2 Relay not allowed.

I'm not sure why I get this. I haven't touched any of the inbound settings in stalwart. The only thing I configured is the next-hop and the directory. All the DNS and MX entries should be correct as they have been working previouesly.

Any ideas what the issue could be?

[mdecimus]

Hi,

It looks like you have not properly configured a local domain. Perhaps the lookup query to resolve local domains is not working. Which directory are you using and have you made sure the domain query works?

[Kidswiss]

Hi @mdecimus

Thanks for the quick reply, I haven't thought about the filter, thanks for the hint!

I'm using the ldap directory and I'm more or less using the default filter for this:

(&(&(objectClass=person)(memberof=cn=mail,ou=groups,dc=secret,dc=local))(|(mail=*@?)(mailAlias=*@?)))

Time to dig out ldapsearch and see if the query actually works or not.

[Kidswiss]

AHA! Found the issue. My ldap server doesn't support substring queries, like the ones used for the domain. I think I can build something around that though.

Thanks for leading me in the right direction!