Issue Summary:
I have two Docker containers running on the same host: a mail server and Vaultwarden (Bitwarden_rs). The mail server provides SMTP and IMAP services and is accessible via a public domain, which points to my server’s IP address. Vaultwarden is just an example, I have the same issue with another service on the machine. I cannot access the mail server due to timeout errors, like if the domain just points into nothingness.
Setup Details:
- Mail Server Docker Container: Runs SMTP and IMAP services, accessible via domain, TLS activated, certificates etc (works fine with Outlook).
- Mailserver: docker-mailserver
- Vaultwarden Docker Container: Provides Bitwarden compatible services, needs to integrate with the mail server for email functionality.
- DNS properly defined with all records necessary.
- Works completely fine with outlook (send and receive).
- Using coolify (basically docker compose) –
- on a root server hosted by netcup (netcups reverse lookup set to my mailserver domain)
Issue Description:
When Vaultwarden tries to connect to the mail server, it just timeouts. The mailserver shows no logs of any client connecting to it. I tried using the mailservers docker hostname, but of course that doesnt work, because the certificate I have is signed for the domain I’m using. I want to use the domain I have registered in Vaultwarden as well.
What I tried:
I’ve spent a long time trying a lot of different things like:
- chainging the /etc/host file
- making sure every dns rule is set (using mxtoolbox)
- going into the docker container, running ping or nslookup to find out if they can resolve the hostname (they can, points to public ip)
- checking dns records by hand using dig
- asking chatgpt in 8 different chats what the problem might be
I’m sure its a rather simple thing I have to do, but I can’t find out what to do.
Thank you for your help!