Comcast residential DNS contact

Christopher Morrow morrowc.lists at
Wed Dec 3 18:37:06 UTC 2014

On Wed, Dec 3, 2014 at 12:54 PM, Grant Ridder <shortdudey123 at> wrote:
> Hi Everyone,
> Thanks for the replies!  After reading them, i am doing some digging into
> DNS RFC's and haven't found much with respect to ANY queries.  Not
> responding with full results to protect against being used in an attack
> makes sense.  However, I find it odd that only 1 of the 4 anycast servers I
> tried would institute this.

it's possible (jason hinted at this) that the servers in question are
not a homogeneous software set... and have different behaviour being
displayed because of that.

Also, just because you sent a packet to 4 different ip addresses
doesn't mean that they didn't end up on one or some of the same hosts
behind loadbalancers/ecmp/etc, right? (so it's not clear you are/can
test this properly from your vantage point)


(what's a bit concerning is my comcast link's not able to talk to
cdns02 at all... over ipv4 at least, v6 works, thankfully I suppose)

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