SMTP Server to Deliver All Mail to User@localhost – Setup Guide

mailsmtp

I'd like to configure an SMTP MTA to accept all mail addressed to any domain and deliver it to my local user account.

It would be very useful for debugging mail sent in some code I'm working on. I'll be running the server locally – no outside world interaction required.

To be clear:

user@gmail.com -> delivered to -> cam8001@localhost

dogs@live.com -> delivered to -> cam8001@localhost

anything@any.domain.co.uk -> delivered to -> cam8001@localhost

Best Answer

I found this article explaining how to do it with postfix.

The key is:

luser_relay = cam8001@localhost
local_recipient_maps =

as explained in the article:

luser_relay is the local user on the machine to catch all email that does not belong to an existing local user. luser_relay documentation.

local_recipient_maps is left blank to stop Postfix from checking if the user exists on the local machine. This is very important, without this line, Postfix will still reject the mail and send a bounce message.

After adding the above two lines to the configuration, apply the changes and restart Postfix.

Related Solutions

SMTP – How to Setup a Local Testing SMTP Server

There are two solutions off the top of my head:

The first is to install postfix and accept the default configuration. Any mail sent to username@server (or just a username if it's all on one server) would be delivered to that specific user. It's fairly easy to get going and can be expanded to a full mail system in the future without much pain.

The second solution, which I leaned of in the Django documentation, is to run:

python -m smtpd -n -c DebuggingServer localhost:25

You may need to run this as root to claim the port. Any mail that is sent to your server will appear on the terminal as long as you have this running. It's great for testing out mail in different applications.

Ubuntu – Easiest way to setup a SMTP server to receive mail

Postfix, Exim, Sendmail and the rest are Mail Transfer Agents and can act as a Mail Submission Agent, Mail Exchange, Mail Transfer Agent, and Mail Delivery Agent. Given the proper cofiguration they will both send and receive email. (If you want to run your own Mail Exchange (MX) server you need a fixed address, and should get your IP address provider to configure your PTR address with your mail servers domain name.)

However, to retrieve email from a service like mailinator you need a program like fetchmail which will read mail from an inbox and pass it to your local MSA (Mail Submission Agent). The trick with a service like mailinator could be to configure pick up addresses dynamically.

Best Answer

Related Solutions

SMTP – How to Setup a Local Testing SMTP Server

Ubuntu – Easiest way to setup a SMTP server to receive mail

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