Showing posts with the label public dns

Spamhaus to block queries from AWS

Hey, email nerds! Are you like me, running various random EC2 instances with scripts or applications that do a bunch of spam and email message analysis, checking (among other things) all the domains and IPs you find? Okay, there aren't millions of us, but I know I'm not…

Querying Spamhaus via Cloudflare DNS? Read this

Remember how I warned that querying Spamhaus via public DNS resolvers wasn't a great idea? "Spamhaus clearly doesn't want to provide this IP reputation data via [public resolvers] and right now it's just a question of how effective they are at blocking it. The…

HOWTO: Query Spamhaus Safely

You'll recall me warning recently that using Spamhaus data to protect your mail server is a bad idea if you're using open or public DNS resolvers . TL;DR? Spamhaus is worried about too much traffic via public channels but blocking is implemented in a way that makes it …

Be careful: Using Spamhaus with open resolvers is bad news

Do you use any of the Spamhaus blocking lists (DNSBLs) to protect yourself from inbound spam and email threats? If so, you're not alone. The Spamhaus data is quite popular and used by many ISPs as a front door gatekeeper for IP (and domain) reputation.