[atlas] NAT conntrack invalid ICMP(v4) type 11 code 0 packets dropped by edge router

On 2015/03/29 9:33 , Gary Gapinski wrote:
> I recently observed a (ICMP type 11 code 0) packet for which the
> reported rejection was for ctr-nue13.atlas.ripe.net, for which target
> there are several active measurements on the probe. An extract of recent
> logs for the related address yielded
> 
> Mar 27 13:43:18 edge kernel: [WAN_LOCAL-2-D]IN=eth0 OUT= MAC=24:a4:3c:05:20:a3:00:01:5c:45:9a:41:08:00 SRC=4.68.111.17 DST=76.188.130.183 LEN=96 TOS=0x00 PREC=0x00 TTL=58 ID=3881 PROTO=ICMP TYPE=11 CODE=0 [SRC=76.188.130.183 DST=78.46.48.134 LEN=68 TOS=0x00 PREC=0x00 TTL=1 ID=57079 PROTO=UDP SPT=20494 DPT=33441 LEN=48 ] 
>
> Is this simply an unfortunate consequence of probe measurement artifacts
> arriving outside of the 30-second conntrack window, or is my local
> configuration adversely affecting such measurements?

It seems to affect hop 9 of the traceroute to ctr-nue13. It is hard to
say if the packet was really 30 seconds late or not.

Philip