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Re: Cloudflare reverse DNS SERVFAIL, normal?


From: David <opendak () shaw ca>
Date: Mon, 29 Aug 2016 15:13:50 -0600

On 2016-08-29 2:46 PM, Jeremy wrote:
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?


Got an example range? All the ones I'm checking here seem fine.

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.

Thanks!
Jeremy



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