I have a mail server (postfix 2.9.6) up and running with 15-20 users, only for internal usage with one single domain, let's call it xyz.mail.lan
email@example.com firstname.lastname@example.org email@example.com … firstname.lastname@example.org
No external relay, or incoming mails from internet side is necessary. It works fine right now.
My goal is to limit the users in sending mails to each other.
- user1 is allowed to send mails only to: user2, user3, user4, user5
- user2 is allowed to send mails only to: user1, user3
- user3 is allowed to send mails only to: user1, user5
- user5 is allowed to send mails only to: user1, user4
I will not have more than 20 users, so I don't mind if my hands has to be dirty with setting up ugly rules for each user.