Taken from Using MacOSX Lion command line mail with Gmail as SMTP
Edit file /etc/postfix/main.cf
sudo vim /etc/postfix/main.cf
and add in the following below the commented out relayhosts :-
myhostname = smtp.gmail.com
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.
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# SASL SUPPORT FOR SERVERS
#
# The following options set parameters needed by Postfix to enable
# Cyrus-SASL support for authentication of mail servers.
#
relayhost = [smtp.gmail.com]:587
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
smtp_use_tls = yes
sudo vim /etc/postfix/sasl_passwd
and enter in the following:-
[smtp.gmail.com]:587 username@gmail.com:password
sudo chmod 600 /etc/postfix/sasl_passwd
sudo postmap /etc/postfix/sasl_passwd
sudo launchctl stop org.postfix.master
sudo launchctl start org.postfix.master
test by sending the contents of a directory to an email address with the following:
tree /var/www/somefolder | mail -s "contents" your@yourdomain.com
If you receive the following error:
send-mail: fatal: chdir /Library/Server/Mail/Data/spool: No such file or directory
you can do the following:
sudo mkdir -p /Library/Server/Mail/Data/spool
sudo /usr/sbin/postfix set-permissions
sudo /usr/sbin/postfix start
as per this question.
NB: If things aint sending / receiving, and you're getting notices, check that the mail servers you're using are actually working!
NOTE: A crappy way to get around Google's
Someone just tried to sign in to your Google Account [youremail]@gmail.com from an app that doesn't meet modern security standards.
is to enable less secure apps on your account: https://www.google.com/settings/security/lesssecureapps. Do this at your own discretion.
sudo nano /etc/postfix/main.cf
add below configs
mydomain_fallback = localhost
mail_owner = _postfix
setgid_group = _postdrop
relayhost = smtp.gmail.com:587
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps=hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
smtp_use_tls = yes
#smtp_tls_security_level = encrypt
#tls_random_source = dev:/dev/urandom
smtp_sasl_mechanism_filter = login
in sasl_passwd
sudo nano /etc/postfix/sasl_passwd
smtp.gmail.com:587 username@gmail.com:password
then send email
date | mail -s test test@yahoo.com
u will receive email from Google with subject "Review blocked sign-in attempt"
from the email you can activate the less secured apps
it works using macos sierra based on above config
hope it helps, as it took me nearly one hour to get it right.