Setup DKIM with Postfix on Ubuntu Server

This post will walk you through setting up DKIM with Postfix on your Ubuntu 18.04, 20.04 or 22.04 Server. Setting up DKIM First, install OpenDKIM which is an open-source implementation of the DKIM sender authentication system. Then add postfix user to opendkim group. Edit OpenDKIM main configuration file. Uncomment the following lines. Replace simple with relaxed/simple. Then…

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Postfix masquerading or changing outgoing SMTP email or mail address

Address rewriting allows changing outgoing email ID or domain name itself. This is good for hiding internal user names. For example:SMTP user: user-01EMAIL ID: [email protected] name: server.domain.com However when user-01 send an email from shell prompt or using php it looks like it was send from [email protected] Postfix MTA offers smtp_generic_maps parameter….

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Useful Postfix Commands

Below are a list of useful commands for managing a postfix mail server: mailq – Use to list items in your mails queues postcat -q MESSAGE_ID – Used to read messages that are in your postfix queue postsuper -d ALL – Delete all queued messages postsuper -d ALL deferred – Delete all messages in…

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