Directadmin does not send or receive email

[hebero]

Hello,

I'm setting up the host, I already have DNS and reverse DNS working and resolving the addresses, but I'm not managing to make the emails work for external addresses (ex: hotmail, gmail), I also don't receive emails from external servers.
Internally the sending between the accounts hosted on the host works normally. I have read several documentation and even so I could not identify what may be happening.

Hostname: ns1.clinitec.net -> ip 177.72.40.14
NS1: ns1.clinitec.net -> ip 177.72.40.14
NS2: ns2.clinitec.net -> ip 177.72.40.205

Has this problem occurred to anyone? Any idea what might be set up wrong? Thank you.

 

[hebero]

This is the log you record in the exim mainlog when you send an email.

2020-04-15 09:18:37 1jOh01-0003ud-9m <= [email protected] H=static-177-72-40-202.mosaicotelecom.com.br ([192.168.100.148]) [177.72.40.202] P=esmtpa A=plain:[email protected] S=729 id=[email protected] T="Teste 15/04" from <[email protected]> for [email protected]
2020-04-15 09:18:37 cwd=/var/spool/exim 3 args: /usr/sbin/exim -Mc 1jOh01-0003ud-9m
2020-04-15 09:20:48 1jOh01-0003ud-9m H=hotmail-com.olc.protection.outlook.com [104.47.70.33] Connection timed out
2020-04-15 09:20:48 1jOh01-0003ud-9m == [email protected] R=lookuphost T=remote_smtp defer (110): Connection timed out

 

[Richard G]

I did a check and it looks like you have port 25 closed.

I hope your hostname is also ns1.clinitec.net otherwise your rDNS record won't be correct. And would also explain you can't send mail through port 25.
Also lots of other mail ports need to be open.

 

[Richard G]

H=static-177-72-40-202.mosaicotelecom.com.br

Hostname is no good either... so you have to fix the closed ports and the hostname, so also the PTR/rDNS record.

 

[hebero]

static-177-72-40-202.mosaicotelecom.com.br is my network's gateway, my PTR is configured on mosaicotelecom's NS1 pointing to ns1.clinitec.net. Do you think the problem could be there beyond the doors? Should ns1.clinitec.net be the gateway?

 

[Richard G]

There are 3 problems.
1.) Port 25 is not open or not reachable from outside, hence you can't receive mail and can have issues sending it.
2.) Your hostname is by default used for Exim's smtp banner. For good RFC practis, your rDNS/PTR record should point to that hostname/smtp banner.
So it doesn't matter if you use ns1.clinitec.net as your hostname and point the rDNS to it, but in that case port 25 should be reachable at the corresponding ip address.
3.) When sending mail the hostname of your gateway is shown "H=static-177-72-40-202.mosaicotelecom.com.br" which is not your domain and does not match the sending domain name which is a problem on itself.

Can you setup your own gateway? I don't know how exactly you mean this, but maybe you can figure it out by the points mentioned here.

If this is a home setup, somebody else needs to help you further, I don't do home setups (no experience with it yet), I can only tell how things should be. On a home setup you might need custom Exim configurations.

 

[hebero]

The problem was at port 25, with the necessary releases, together with our network manager, emails started to work for external addresses. I really didn't know that even using other ports, port 25 needs to be open for the email system to work.

Thank you for your help.

 

[Richard G]

Yep. Even when users do use other ports, port 25 is the basic port used by mailservers between themselves to send and deliver mail.
That's why I mentioned it in the first reply.

Glad it's fixed. As for my help, you're welcome.