sudo dpkg-reconfigure postfix
I followed the instructions up to the point of installing ''s-nail'', I prefer ''mutt''.
sudo apt-get install mutt
''mutt'' worked right away, sending an email to my personal email account, and receiving a reply from it.
===== Testing & Checking =====
Sent a test email to: [[http://www.checktls.com/perl/TestSender.pl|Test sender TLS]].
SUCCESSFUL
SUCCESSFUL //email/test From:
Your email was sent securely using TLS.
====== Useful Tricks ======
===== Migrate Mailbox =====
# Change to home directory
cd ~
# Copy mailbox data from backup
sudo cp -r /mnt/volume_lon1_01/disk_backup/home/david/Maildir .
# Fix file and directory ownership
sudo chown -R david:david Maildir
===== bounce (forward) email =====
In ''mutt'' to bounce (forward) an email to another address (say a HTML email forward to a regular mailbox), press ''b'' when the email is selected and then put the address into the application and hit enter.
===== Requirements for Gmail to receive emails =====
==== MX Records ====
==== Google Domain TXT record ====
* https://support.google.com/a/answer/183895?hl=en
==== PTR Records ====
> Mail servers must meet a number of requirements to prevent their messages from being blocked, e.g. have a PTR record. The use of authentication methods such as SPF, DKIM or DMARC minimize the chance that messages are marked as spam.
* https://stackoverflow.com/questions/15771932/the-ip-youre-using-to-send-mail-is-not-authorized-to-send-email-directly-to-our
* https://support.google.com/mail/answer/81126
* Digital Ocean: https://docs.digitalocean.com/products/networking/dns/how-to/manage-records/#ptr-rdns-records
====== Mixed Links ======
Documentation
* DigitalOcean Community Documentation (e-mail) 20.04:
* [[https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-postfix-on-ubuntu-20-04|How To Install and Configure Postfix on Ubuntu 20.04]]
* DigitalOcean Community Documentation (e-mail) Original:
* [[https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-postfix-on-ubuntu-16-04|How To Install and Configure Postfix on Ubuntu 16.04]]
* Part 1: [[https://www.digitalocean.com/community/tutorials/how-to-set-up-a-postfix-e-mail-server-with-dovecot|How To Set Up a Postfix E-Mail Server with Dovecot]]
* Part 2: [[https://www.digitalocean.com/community/tutorials/how-to-set-up-a-postfix-email-server-with-dovecot-dynamic-maildirs-and-lmtp|How To Set Up a Postfix Email Server with Dovecot: Dynamic Maildirs and LMTP]]
Various links used in debugging under older installation
* [[https://unix.stackexchange.com/questions/108097/suppresss-mail-does-not-exist-in-mutt|Suppresss “~/Mail does not exist” in mutt]]. Just create the dir and have done with it.
* [[https://serverfault.com/questions/579138/is-it-ok-to-use-self-signed-certificates-for-smtp-transport|Is it ok to use self-signed certificates for smtp transport?]]
* [[http://www.checktls.com/perl/TestSender.pl|Test sender TLS]]
* [[https://www.linuxquestions.org/questions/ubuntu-63/postfix-emails-send-outgoing-mail-with-wrong-domain-name-785746/|Postfix emails send outgoing mail with wrong domain name]]
* [[https://askubuntu.com/questions/87665/how-do-i-change-the-hostname-without-a-restart|How do I change the hostname without a restart?]] - ''sudo hostname roman-halliday.com''
* [[https://www.digitalocean.com/community/tutorials/how-to-create-a-spf-record-for-your-domain-with-google-apps|How To Create a SPF Record For Your Domain with Google Apps]]
Email server testing site:
* [[https://mxtoolbox.com/domain/roman-halliday.com/]]