Configuring Docker Mailserver to Send Emails on Behalf of Another Domain
Docker Mailserver is a popular open-source mail transfer agent (MTA) that can be easily containerized and deployed in various environments. In this article, we will discuss how to configure Docker Mailserver to send emails on behalf of another domain.
Prerequisites
Before we begin, ensure that you have the following:
- A running instance of Docker Mailserver
- Access to the Docker host and the ability to run Docker commands
- A domain name (e.g.,
domain2.com) for which you want to send emails - An email address (e.g.,
[email protected]) from the domain for which you want to send emails
Configuring Docker Mailserver
To configure Docker Mailserver to send emails on behalf of another domain, you need to modify the configuration file. By default, Docker Mailserver stores the configuration file in the /etc/docker-mailserver directory.
First, create a new file named extraconfig.ini in the /etc/docker-mailserver directory and add the following content:
smtp-relay-hosts = ["mail.domain1.com:587"]
smtp-relay-auth-username = "username"
smtp-relay-auth-password = "password"
smtp-relay-auth-mechanism = "PLAIN"
smtp-relay-auth-from-domain = "domain2.com"
Replace the following values:
mail.domain1.com: The hostname or IP address of the mail server that will receive the emailsusername: The username for authentication to the mail serverpassword: The password for authentication to the mail serverdomain2.com: The domain name for which you want to send emails
Next, you need to modify the config.ini file to include the new configuration file. Add the following line to the config.ini file:
include = /etc/docker-mailserver/extraconfig.iniSave the changes and restart the Docker Mailserver container:
docker-compose restart
Testing the Configuration
To test the configuration, you can send a test email using the following command:
echo "Test email" | mail -s "Test Subject" [email protected]
If the configuration is correct, the email should be delivered to the recipient's mailbox.
References
In this article, we discussed how to configure Docker Mailserver to send emails on behalf of another domain. We covered the prerequisites, the steps to configure Docker Mailserver, and how to test the configuration. With this configuration, you can use Docker Mailserver to send emails from any domain name, making it a versatile and powerful tool for email delivery.