With it’s own dedicated net connection and the blessing of the ISP to send as much email as we can through it. At this point I’ve managed to get the real bitching people off the mailing list so that’s good.
But today – actually plugged in and activated the old IBM eServer x306 8836 that I’d given to the campaign. It does sound a bit like a loud fan. But that noise is well worth what it will allow us to do. The server itself is setup as a RAID 1 or mirroring array. It’s only an 80GB array but replacement drives in the half a terabyte range – a pair can be had for < $100. I’m planning on doing that with my other x306.
So I had tried getting Postfix to send email outside the network to no success. It kept getting bounced by external SMTP servers with 550 errors. A 550 error is basically a server rejecting a message as spam. To get around it you have to make sure the FQDN for your server matches the IP addresses you’re sending from. In other words say mail01.girouxforgovenror2014.com has an ip of 18.104.22.168. The host registration for mail01 has to belong to that IP address.
So I logged onto Bluehost and created the subdomain I show above. Then I went into the Domain Zones and pointed mail01 to what is our publicly appearing IP address for outbound mail only. And it works, of course I knew it would. You see the entirety of the anti-spam effort rests upon RDNS or Reverse DNS. The remote mail server or MTA sees the connection coming from 22.214.171.124 but it then does a lookup on the IP address to see if the domain matches that of the sending party in the email headers. If it doesn’t, 550 error and blocked. If it does – the email flows.
Another issue I had
#mynetworks = 127.0.0.1/8 [::ffff:127.0.0.0]/104 [::1]/128
That pound sign means comment the line out. As soon as I turned that off I was able to send email out from inside the new network. Yippee!