Integrating Amply with Postfix is easy and can be done in just a few minutes.

Update main.cf

Find your Postfix config file, typically at /etc/postfix/main.cf and add the following:

smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
smtp_sasl_tls_security_options = noanonymous
smtp_tls_security_level = encrypt
header_size_limit = 4096000
relayhost = [smtp.sendamply.net]:587

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Update your credentials

Now you need to specify your credentials in the file /etc/postfix/sasl_passwd (you'll likely need to create it):

[smtp.sendamply.com]:587 yourAmplySMTPUsername:yourAmplyAccessToken

You can find your SMTP username from your General Settings page.

Next, make sure the file has restricted read and write access only for root, and use the postmap command to update Postfix's hashtables to use this new file:

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

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Restart Postfix

Finally, restart Postfix:

sudo systemctl restart postfix

Postfix should now be configured to send mail through Amply!

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Troubleshooting

If you receive an error "no mechanism available", you are likely missing some SASL libraries.

Install the missing module dependency using apt-get (i.e., Debian, Ubuntu):

$ apt-get install libsasl2-modules

Or using a yum (i.e., RedHat, Fedora, CentOS):

$ yum install cyrus-sasl-plain

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Port 587 is blocked

If port 587 is not working for you, please try 2525 in your postfix config. Some ISP's block email ports in an effort to reduce spam.