Can't send local mail message between users on linux

Question

In https://unix.stackexchange.com/a/21336/99621 it says that if you do

echo 'body' | mail -s 'subject' myuser

It will send a mail message to the myuser linux account on the local system that this user can check with the mail command. I tried sending mail to my own user account by running that command and it executes without any problems (no output in terminal and 0 exit code).

But when I type mail to check for mail, it says No mail for myuser.

If I replace the above mail sending command with one that doesn't exist, such as notexistinguser, the command still executes without any problems.

How can I send mail to a local Linux user account and check it? (I'm on a pretty minimal installation Archlinux.) I've also installed Postfix which is up and running with the default configuration, thought it might have interfered so I stopped it but still the same problem.

Answer 1

For mail to work as expected it requires a mail transfer agent (MTA), such as Sendmail, or Postfix. A minimal installation of Arch Linux includes neither.

You're on the right track installing Postfix. The Arch wiki has a guide for configuring Postfix specifically for local mail delivery here: Postfix - Local mail.

After modifying your /etc/postfix/main.cf configuration file with the changes suggested in the wiki article, you'll want to start the Postfix daemon with the following command:

$ systemctl start postfix

To permanently enable local mail delivery thereafter:

$ systemctl enable postfix