Using GMail as a relay with Postfix
Fri 22 July 2011
I fiddled a bit with this, so I thought I'd do a no-nonsense guide to doing this. There are other guides, but a lot of them are incomplete and will leave you with queueing issues or annoyances.
The science bit:
smtp_use_tls = yes 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 # Send all mail through smtp.gmail.com relayhost = smtp.gmail.com # Stop getting a catpcha, hopefully. smtp_destination_rate_delay = 60 relay_destination_rate_delay = 60
Then, edit /etc/postfix/sasl_passwd:
It doesn't have to be an @gmail account, it can be a GAFYD account, once you've logged into it once to activate it.
Then just generate the map file for the sasl_passwd file and reload. As root:
postmap sasl_passwd postfix reload
And you're done. Monitor your queue a few times over the first few days to make sure stupid stuff hasn't happened (the delay between mails might get tweaked), but in general this has worked for me.