Postfix smtp relay on OS X Yosemite 10.10

I’m lazy, and for email testing this is great. Who doesn’t need an email relay at some point?¬†As there was no off the shelf solution, here it is for Yosemite.

Define the relay host:
sudo vim /etc/postfix/
Add section after the existing ‘relayhost’ example:
relayhost = []: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_sasl_mechanism_filter = plain

Add your account for the relay to use.
sudo vim /etc/postfix/sasl_passwd

Make sure it starts at boot. If you don’t want this, skip this!
sudo vi /System/Library/LaunchDaemons/org.postfix.master.plist
add this:

sudo chmod 600 /etc/postfix/sasl_passwd
sudo postmap /etc/postfix/sasl_passwd

Then stop postfix:
sudo launchctl stop org.postfix.master
And start it again (so it reads the config changes):
sudo launchctl start org.postfix.master
sudo postfix start

Check it’s listening:
netstat -an | grep LISTEN | grep 25
It should output something like this:
tcp6 0 0 ::1.25 *.* LISTEN
tcp4 0 0 *.* LISTEN

You can test it like so:
df -kH | mail -s “contents”

1) You can screw your postfix if you don’t pay attention. Be carefull.
2) gmail was used as an example. I’m not endorsed, sponsored or whatever.

This is based on:
Using MacOSX Lion command line mail with Gmail as SMTP
Mac OS X 10.10 Yosemite Postfix SASL authentication failed

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