FYI, the usual 75ms SJC to IAD on UUnet (AS701) backbone has been over 110ms for about an hour. 2 0.so-0-2-0.XL1.SJC1.ALTER.NET (152.63.54.18) [AS 701] 0 msec 1 msec 1 msec 3 * 0.xe-7-0-2.XL3.IAD8.ALTER.NET (152.63.32.230) [AS 701] 163 msec 140 msec No end-to-end loss observed. -mark
Mark, 1. Doesn't Verizon/MCI/UUnet/Alter.net use ICMP prioritisation on their routers? Packet loss or latency seen at an individual router hop is usually (not always, but usually) indicative of that. 2. You stripped hops 4 onward from your output, which doesn't help analysis at all; if latency is truly a problem (oversaturated link, etc.), it "trickles down" through each subsequent hop, 3. You didn't provide a return-path traceroute (e.g. dst-->src) so it's hard to say "the problem is with Verizon" necessarily. (I'm inclined to believe you given their history (believe me, I'm more than familiar with them at this point), but still...) This may benefit you: http://www.nanog.org/meetings/nanog47/presentations/Sunday/RAS_Traceroute_N4... Finally, and maybe the most important point of all: If no loss is seen end-to-end (source-to-dest) then what's the concern? Or are you saying there's no packet loss end-to-end but there is latency end-to-end? (Your Email doesn't explicitly say that, and I don't want to make assumptions...) -- | Jeremy Chadwick jdc@koitsu.org | | UNIX Systems Administrator http://jdc.koitsu.org/ | | Mountain View, CA, US | | Making life hard for others since 1977. PGP 4BD6C0CB | On Thu, Oct 18, 2012 at 09:47:49AM -0700, Mark Kent wrote:
FYI, the usual 75ms SJC to IAD on UUnet (AS701) backbone has been over 110ms for about an hour.
2 0.so-0-2-0.XL1.SJC1.ALTER.NET (152.63.54.18) [AS 701] 0 msec 1 msec 1 msec 3 * 0.xe-7-0-2.XL3.IAD8.ALTER.NET (152.63.32.230) [AS 701] 163 msec 140 msec
No end-to-end loss observed.
-mark _______________________________________________ Outages mailing list Outages@outages.org https://puck.nether.net/mailman/listinfo/outages
Please note "FYI" at the beginning of my message. I wasn't asking for help or analysis, I was just pointing out something that, based on our monitoring for the past nine months, is uncommon between the two direct-attached ports we monitor (in SJC and IAD). Thanks, -mark On 10/18/12 10:02 AM, Jeremy Chadwick wrote:
Mark,
1. Doesn't Verizon/MCI/UUnet/Alter.net use ICMP prioritisation on their routers? Packet loss or latency seen at an individual router hop is usually (not always, but usually) indicative of that.
2. You stripped hops 4 onward from your output, which doesn't help analysis at all; if latency is truly a problem (oversaturated link, etc.), it "trickles down" through each subsequent hop,
3. You didn't provide a return-path traceroute (e.g. dst-->src) so it's hard to say "the problem is with Verizon" necessarily. (I'm inclined to believe you given their history (believe me, I'm more than familiar with them at this point), but still...)
This may benefit you:
http://www.nanog.org/meetings/nanog47/presentations/Sunday/RAS_Traceroute_N4...
Finally, and maybe the most important point of all:
If no loss is seen end-to-end (source-to-dest) then what's the concern? Or are you saying there's no packet loss end-to-end but there is latency end-to-end? (Your Email doesn't explicitly say that, and I don't want to make assumptions...)
participants (2)
-
Jeremy Chadwick -
Mark Kent