Cloudflare reverse DNS SERVFAIL, normal?

Jeremy jbaino at
Mon Aug 29 20:46:05 UTC 2016

We're seeing a huge uptick in reverse dns lookup failures across an app,
99% are all for Cloudflare ip addresses.

Instead of seeing a PTR or NXDOMAIN we're getting back SERVFAIL.

Does anyone know if this is a standard response from them? Do they not have
reverse DNS setup for their networks?

Trying to narrow this down to see if it's a result in a change in how our
application handles these errors or if there's an issue going on with
cloudflare's DNS setup.


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