Best practice on TCP replies for ANY queries

ML ml at kenweb.org
Wed Dec 11 18:19:35 UTC 2013


On 12/11/2013 1:06 PM, Anurag Bhatia wrote:
>
> I am sure I am not first person experiencing this issue. Curious to hear
> how you are managing it. Also under what circumstances I can get a
> legitimate TCP query on port 53 whose reply exceeds a basic limit of less
> then 1000 bytes?
>
>
>

I'm not a DNS guru so I don't have an exact answer.  However my gut
feeling is that putting in a place a rule to drop or rate limit DNS
replies greater than X bytes is probably going to come back to bite you
in the future.

No one can predict the future of what will constitute legitimate DNS
traffic.




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