The 4.2.2.x machines are known to have some pretty heavy handed ICMP rate limits. I'd suggest trying to hit anything on level3 but those... Nick Olsen Network Operations (855) FLSPEED x106 ---------------------------------------- From: "Khurram Khan" <kkhan@brokenflea.net> Sent: Tuesday, October 07, 2014 4:48 PM To: "nanog@nanog.org" <nanog@nanog.org> Subject: Weird Issues within L3 Hi Group, We have a couple of circuits , internet facing with Level 3 and from our edge in San Diego, seeing some packet loss when trying a ping to 4.2.2.4, sourcing from 63.214.184.3. anyone seeing a similar issue ? Packet sent with a source address of 63.214.184.3 !.!!!.!!!!!!!!!!!!!...!!!..!!!!!!.!!.!!!!!!.!..!!.!!.!!!!!!!!!!!!!!!!! !!!!!!!!!.!!.!!!..!!!!!.!!!!.! Success rate is 80 percent (80/100), round-trip min/avg/max = 12/13/16 ms

On 10/07/2014 11:36 AM, Khurram Khan wrote:

Hi Group,

We have a couple of circuits , internet facing with Level 3 and from our edge in San Diego, seeing some packet loss when trying a ping to 4.2.2.4, sourcing from 63.214.184.3. anyone seeing a similar issue ?

Packet sent with a source address of 63.214.184.3 !.!!!.!!!!!!!!!!!!!...!!!..!!!!!!.!!.!!!!!!.!..!!.!!.!!!!!!!!!!!!!!!!! !!!!!!!!!.!!.!!!..!!!!!.!!!!.! Success rate is 80 percent (80/100), round-trip min/avg/max = 12/13/16 ms

I'm not with level3, but the pattern looks exactly like what happens when a destination node has rather severe rate-limiting in place, and multiple people are sending ICMP. Try spacing your ping packets. On Linux, the command switch is "ping -i 3" to send packets every three seconds; for MTR it's "mtr -i 3" -- If you are using something else, there should be an "interval" parameter that you can set to minimize rate-limiting effects. Have you tried sending real traffic to 4.2.2.4, and looking at the packet traffic?