Maintained by: NLnet Labs

[Unbound-users] Maximum size of UDP responses?

Fri Apr 19 15:43:05 CEST 2013

Hi Wouter,

Here is a patch to implement only "max-udp-size" (a revised version).
I hope this would be applied to mainline.

 max-udp-size: <number>
   Maximum UDP response size.
   Valid values are 512 to 4096. Default is 4096.

In spite of my allow_minimal patch, Unbound should implement
max-udp-size option and defaults to 4096.
Because currently Unbound's response size has no limit and it can be
dangerous high-amplification-rate reflector if Unbound is mistakenly
configured as open-resolver. Also useful if we want to avoid IP

 Daisuke HIGASHI <daisuke.higashi at>
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