Failed to send to another mail server in the same environment

[brenoacp]

Hello everyone!
I have the following environment:
Domain AD in company.com.br format (not configured as empresa.local)
Multi-domain email server 1: empresa.com.br, empresa2.com.br and empresa3.com.br
We will migrate all domains to Zimbra, but the migration will be in parts, one domain at a time.
The installation of Zimbra was done based on the domain.com.com.br and the dns used by this server are the AD of the forest. (Zimbra server is not joined to the domain)
The problem is that in tests we try to send an email from Zimbra of the domain empresa2.com.br to the domain empresa.com.br that is in the old server without success.
I renamed the domain empresa.com.br to empresa9.com.br and when I try to send the email it is stopped in the queue as below.
The IP listed below is one of the AD server and not the old mail server.
I've already done the DNS exchange for a public DNS more unsuccessfully.


-Queue ID- --Size-- ---- Arrival Time ---- -Sender / Recipient -------
126061622103 2148 Fri Apr 7 15:08:06 user@empresa2.com.br
(Connect to empresa.com.br [192.168.1.60]: 25: Connection refused)
User2@company.com.br


Is there a way to route emails to a particular domain to query directly on the internet?
Do you think it would solve this problem?


Best regards

Breno Padovan

[DualBoot]

Hello,

for what I understand and read, the problem seems to be related to FireWall or no SMTP server listening on port 25 at destination.