Tek's Domain


How DNSBLs Work

2021-06-27 4 min read Email Security Sysadmin stuff Tech explained Teknikal_Domain Unable to load comment count

Ff you’ve dealt with email for any longer than 5 minutes (as an administrator), you already know it’s a mess. There’s so many security measures, so many checks, so many things to combat bad actors and spam. What if we had some way to have some service publish a list of bad DPs, and mail servers could quickly check that mid-transaction so they can have up-to-date information as to if the in-flight message should actually be accepted or not?

Well, we have exactly that. Enter: the DNS Blacklist.

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AbuseIPDB Checking With Postfix

2021-01-28 11 min read Programming Security Software Sysadmin stuff Tech Teknikal_Domain Unable to load comment count

So if you’ve not heard, there’s this website called AbuseIPDB, which, no affiliation, is a website where webmasters can submit reports of abusive IP addresses, and then query those reports, either manually, or using their REST API. And this is how I did exactly that, to help cut down some of the spam on my email server. Let’s get started.

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