Setup a Local Only SMTP Email Server (Linux, Unix, Mac)

Email Server (Linux, Unix, Mac).md

Setup a Local Only SMTP Email Server (Linux, Unix, Mac)

1 - Point localhost.com to your machine

Most of programs will not accept an email using just @localhost as domain. So, edit /etc/hosts file to make the domain localhost.com point to your machine, including this content to the file:

127.0.0.1 localhost.com

2 - Install Postfix

Fedora/CentOS/RHEL: sudo yum install postfix

Ubuntu: sudo apt-get install postfix

MacOSX: Postfix is already installed by default.

3 - Configure Postfix to Local only

• During postfix install process, the configure text dialog will display five options:

  General type of mail configuration: 
  
  No configuration
  Internet Site
  Internet with smarthost
  Satellite system
  Local only
  

• Select "Local Only".

• For the domain name, use the default suggested and finish the install.

4 - Configure a Catch-all Address

Enabling this, you can use any email address ending with "@localhost" or "@localhost.com".

Example: here, my unique account is [email protected]. But while testing systems, I can use any address like [email protected], [email protected], etc, because all will be redirected to [email protected]

• If not exists, create file /etc/postfix/virtual: sudo nano /etc/postfix/virtual
• Add the following 2 lines content, replacing <your-user> with your Unix user account:

@localhost <your-user>
@localhost.com <your-user>

• Save and close the file.
• Configure postifx to read this file:
  • Open /etc/postfix/main.cf: sudo nano /etc/postfix/main.cf
  • And check if this line is enabled, or add it if not exists: virtual_alias_maps = hash:/etc/postfix/virtual
• Activate it: sudo postmap /etc/postfix/virtual
• Reload postfix: sudo systemctl restart postfix
• If you're under non systemd distro, like Ubuntu 14.04, service restart command probably is: sudo service postfix reload

5 - Install Thunderbird

Ubuntu: sudo apt-get install thunderbird

6 - Configure Thunderbird

• Skip the welcome screen (click in the button to use existing accounts);
• Click in the Settings button at top right (similar to Chrome settings) then click on Preferences > Account Settings
• Under Account Actions choose "Add Other Account"
• Select "Unix Mailspool (Movemail)"
• Your account will be <your-user>@localhost (of course, replace <your-user> with your user account). Don't use <your-user>@(none), use <your-user>@localhost
• Ingoing and Outgoing server will be: localhost
• Restart (close and reopen) Thunderbird.

7 - Start your Mail Spool file

• This step have two purposes: test your install and stop the Unable to locate mail spool file. message.
• Using Thunderbird, send new email to <your-user>@localhost, replacing <your-user> with your user account
• Click on "Get Mail"
• Test catch-all: send new email to averagejoe@localhost
• Click on "Get Mail" and you'll see the message at Inbox.