- We will start with a trusty DigitalOcean instructional – at least step 1 of that instructional.
- I want to send mail using mailgun, which allows for ports 25, 587 and 465 (SSL/TLS). I’ll use 587 which is called submission in postfix terminology, I guess due to 587 being the proper port for TLS email submission. Because I want to use encryption (SASL) (or whatever), I need to setup Postfix accordingly. I changed my Postfix config file as such
ubuntu@machine_name:~$ sudo nano /etc/postfix/main.cf
#various stuff above relayhost = [smtp.mailgun.org]:submission mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 mailbox_size_limit = 20000000 recipient_delimiter = + inet_interfaces = all inet_protocols = all smtp_sasl_auth_enable = yes smtp_tls_security_level = encrypt smtp_sasl_security_options=noanonymous smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
Some of these settings are related to the DigitalOcean instructional, such as custom mailbox_size_limit. Make sure all the smtp settings are there