Configure SMTP
Installing mail server on Ubuntu 19.10 LTS Server
Install postfix
Install mailutils
(optional) mailjet.com
Reference
https://www.linuxbabe.com/mail-server/setup-basic-postfix-mail-sever-ubuntu
https://www.linuxbabe.com/mail-server/postfix-smtp-relay
https://app.mailjet.com/docs/spf-dkim-guide
https://linuxaria.com/pills/how-to-setup-postfix-to-forward-email-to-another-email-account-on-debianubuntu
