..todo.. - Please contribute more to help others debug this package ## Enable verbose debugging output You may find it useful to enable the [DMS_DEBUG](https://github.com/tomav/docker-mailserver#dms_debug) environment variable. ## Invalid username or Password 1. Login Container ```bash docker exec -it bash ``` 2. Check log files `/var/log/mail` could not find any mention of incorrect logins here neither in the dovecot logs 3. Check the supervisors logfiles `/var/log/supervisor` You can find the logs for startup of fetchmail, postfix and others here - they might indicate problems during startup 4. Make sure you set your hostname to 'mail' or whatever you specified in your docker-compose.yml file or else your FQDN will be wrong ## Installation Errors 1. During setup, if you get errors trying to edit files inside of the container, you likely need to install vi: ``` bash sudo su docker exec -it apt-get install -y vim ``` ## Testing Connection I spent HOURS trying to debug "Connection Refused" and "Connection closed by foreign host" errors when trying to use telnet to troubleshoot my connection. I was also trying to connect from my email client (macOS mail) around the same time. Telnet had also worked earlier, so I was extremely confused as to why it suddenly stopped working. I stumbled upon fail2ban.log in my container. In short, when trying to get my macOS client working, I exceeded the number of failed login attempts and fail2ban put dovecot and postfix in jail! I got around it by whitelisting my ipaddresses (my ec2 instance and my local computer) ```bash sudo su docker exec -ti mail bash cd /var/log cat fail2ban.log | grep dovecot # Whitelist ip addresses: fail2ban-client set dovecot addignoreip # Server fail2ban-client set postfix addignoreip fail2ban-client set dovecot addignoreip # Client fail2ban-client set postfix addignoreip # this will delete the jails entirely - nuclear option fail2ban-client stop dovecot fail2ban-client stop postfix ``` ## Send email is never received Some hosting provides have a stealth block on port 25. Make sure to check with your hosting provider that traffic on port 25 is allowed Common hosting providers known to have this issue: - [Azure](https://docs.microsoft.com/en-us/azure/virtual-network/troubleshoot-outbound-smtp-connectivity) - [AWS EC2](https://aws.amazon.com/premiumsupport/knowledge-center/ec2-port-25-throttle/)