I’ve been using DNS Stuff for years now. There some useful tools there and over time they’ve been refined and expanded on. The top tool is DNSreport which runs a series of tests against the nameservers for a given domain. It’s pretty much the first place I go when I run into DNS issues.

Other tools I find myself returning to time and again:

IP Information

An easy way to get an idea of where an IP address is geographically.

ISP Cached DNS Lookup

Useful for when you’ve changed a zone and want to see where the old info is still being used.

Spam Database Lookup

Great to check when you’re about to get a new IP or want to check an existing address for past abuses.

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