021e942c4c
Consistency pass, formatting cleanup and fixes, introduce admonitions, add front-matter. --- docs: Add front-matter --- docs: Fix and format links - Some links were invalid (eg files moved or renamed) - Some were valid but had invalid section headers (content removed or migrated) - Some use `http://` instead of `https://` when the website supports a secure connection. - Some already used the `[name][reference]` convention but often with a number that wasn't as useful for maintenance. - All referenced docs needed URLs replaced. Opted for the `[name][reference]` approach to group them all clearly at the bottom of the doc, especially with the relative URLs and in some cases many duplicate entries. - All `tomav` references from the original repo prior to switch to an organization have been corrected. - Minor cosmetic changes to the `name` part of the URL, such as for referencing issues to be consistent. - Some small changes to text body, usually due to duplicate URL reference that was unnecessary (open relay, youtous) - Switched other links to use the `[name][reference]` format when there was a large group of URLs such as wikipedia or kubernetes. Github repos that reference projects related to `docker-mailserver` also got placed here so they're noticed better by maintainers. This also helped quite a bit with `mermaid` external links that are very long. - There was a Github Wiki supported syntax in use `[[name | link]]` for `fetchmail` page that isn't compatible by default with MkDocs (needs a plugin), converted to `[name][reference]` instead since it's a relative link. --- docs: Update commit link for LDAP override script Logic moved to another file, keeping the permalink commit reference so it's unaffected by any changes in the file referenced in future. --- docs: Heading corrections Consistency pass. Helps with the Table of Contents (top-right UI) aka Document Outline. docs: codefence cleanup --- docs: misc cleanup --- docs: Add Admonitions Switches `<details>` usage for collapsible admonitions (`???`) while other text content is switched to the visually more distinct admoniton (`!!!` or `???+`) style. This does affect editor syntax highlighting a bit and markdown linting as it's custom non-standard markdown syntax.
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title
| title |
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| Troubleshooting | Debugging |
!!! info "Contributions Welcome!" Please contribute your solutions to help the community ❤️
Enable Verbose Debugging Output
You may find it useful to enable the DMS_DEBUG environment variable.
Invalid Username or Password
-
Shell into the container:
docker exec -it <my-container> bash -
Check log files in
/var/log/mailcould not find any mention of incorrect logins here neither in the dovecot logs. -
Check the supervisors logs in
/var/log/supervisor. You can find the logs for startup of fetchmail, postfix and others here - they might indicate problems during startup. -
Make sure you set your hostname to
mailor whatever you specified in yourdocker-compose.ymlfile or else your FQDN will be wrong.
Installation Errors
During setup, if you get errors trying to edit files inside of the container, you likely need to install vi:
sudo su
docker exec -it <my-container> 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)
sudo su
docker exec -ti mail bash
cd /var/log
cat fail2ban.log | grep dovecot
# Whitelist IP addresses:
fail2ban-client set dovecot addignoreip <server ip> # Server
fail2ban-client set postfix addignoreip <server ip>
fail2ban-client set dovecot addignoreip <client ip> # Client
fail2ban-client set postfix addignoreip <client ip>
# 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: