What’s this? These are somewhat random jots I made while setting up an authoritative BIND server, so that a simple VPS machine can function standalone. Well, almost standalone, as it takes some help from a slave DNS to supply the second DNS entry. But even if that slave goes away suddenly, the show will go [...]
But why? Fact number one: Running your own mail server is the most likely cause for messing up, and that can mean an intrusion to the server or just turning it into a public toilet for spam. Nevertheless, if mail delivery is important to you, there’s probably no way around. And I’m not talking about [...]
Introduction This is an explicit walkthrough on how a domain name is resolved. Doing the recursion manually, that is. And then some remarks on the mess with DNS glue records. Getting the root servers $ dig NS . ; <<>> DiG 9.11.3-1ubuntu1.2-Ubuntu <<>> NS . ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: [...]
Gmail is definitely the leader in the field of email services, and their spam filter is actually very good. From my own experience with setting up a mail server, I can tell that it’s not all that easy to make Gmail’s incoming mail servers even talk with you. So the larger part of spammer don’t [...]
Intro Whether you just want your non-Gmail personal email to get through, or you have a website that produces transactional emails (those sent by your site or web app), there’s a long fight with spam filters ahead. The war against unsolicited emails will probably go on as long as email is used, and it’s an [...]
This is a quick overview of the parts of an SMTP session that are relevant to SPF and mail server setup. Just a sample SMTP session For a starter, this is what an ESMTP session between two mail servers talking on port 25 can look like (shamelessly copied from this post, which also shows how [...]