[191223] in North American Network Operators' Group
Re: Cloudflare reverse DNS SERVFAIL, normal?
daemon@ATHENA.MIT.EDU (David)
Mon Aug 29 17:13:56 2016
X-Original-To: nanog@nanog.org
To: nanog@nanog.org
From: David <opendak@shaw.ca>
Date: Mon, 29 Aug 2016 15:13:50 -0600
In-Reply-To: <CAJCOWev9n7i+dAhrKTqN=vvBj7qL95y7_5wAwTB9yCeyoYMyBA@mail.gmail.com>
Errors-To: nanog-bounces@nanog.org
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
>
