Hi.

We installed OP (12.4.3) via docker on a linux host:

#!/bin/bash
docker run -d -p 8080:80 \
--name openproject \
--restart unless-stopped \
 -e OPENPROJECT_SECRET_KEY_BASE=secret \
 -e OPENPROJECT_HOST__NAME=openproject.domain.de:8080 \
 -e OPENPROJECT_HTTPS=false \
 -e OPENPROJECT_LOG__LEVEL=debug \
 -v /opt/docker/openproject/pgdata:/var/openproject/pgdata \
 -v /opt/docker/openproject/assets:/var/openproject/assets \
openproject/community:12

I configured SMTP as follows:

• Type: smtp
• Server: our.mail.server
• Port: 25
• HELO: our-domain
• Auth: none

Those settings are correct and working in many other applications. However, while testing, I just get (Net::ReadTimeout with #<Socket:(closed)>). after 3 secs.

accessing the container let me successfully ping the mail server and talk to it:

root@7b8fcde72bd0:/# telnet mail.ourserver.de 25
Trying x.x.x.x...
Connected to mail.ourserver.de.
Escape character is '^]'.
220 xxx ESMTP Sendmail 8.15.2/8.15.2/Debian-3; Wed, 1 Feb 2023 14:25:48 +0100; (No UCE/UBE) logging access from: [](FAIL)-[]
HELP
214-2.0.0 This is sendmail version 8.15.2
214-2.0.0 Topics:
214-2.0.0       HELO    EHLO    MAIL    RCPT    DATA
214-2.0.0       RSET    NOOP    QUIT    HELP    VRFY
214-2.0.0       EXPN    VERB    ETRN    DSN     AUTH
214-2.0.0       STARTTLS
214-2.0.0 For more info use "HELP <topic>".
214-2.0.0 To report bugs in the implementation see
214-2.0.0       http://www.sendmail.org/email-addresses.html
214-2.0.0 For local information send email to Postmaster at your site.
214 2.0.0 End of HELP info

So, where is the problem? The openproject docker log tells me nothing..

Thanks in advance!