Comcast Routing?

[jake223]

Ever since the Comcast circuit was turned on today I have been getting odd routing to the steadfast network,

Tracing route to ip88.208-100-14.static.steadfast.net [208.100.14.88]
over a maximum of 30 hops:

  1     *        *        *     Request timed out.
  2     5 ms     6 ms     8 ms  ge-1-2-ur01.noblesville.in.indiana.comcast.net [
68.85.179.9]
  3     5 ms     9 ms     6 ms  pos-0-10-0-0-ar01.indianapolis.in.indiana.comcas
t.net [68.86.90.174]
  4    13 ms    15 ms    15 ms  pos-0-0-0-0-cr01.nashville.tn.ibone.comcast.net
[68.86.90.173]
  5    33 ms    27 ms    27 ms  pos-0-4-0-0-cr01.atlanta.ga.ibone.comcast.net [6
8.86.85.26]
  6    34 ms    31 ms    32 ms  pos-1-10-0-0-cr01.chicago.il.ibone.comcast.net [
68.86.85.61]
  7    33 ms    37 ms    35 ms  68.86.89.194
  8    33 ms    32 ms    35 ms  ip17.208-100-32.static.steadfast.net [208.100.32
.17]
  9    31 ms    34 ms    32 ms  ip88.208-100-14.static.steadfast.net [208.100.14
.88]

Trace complete.

Tracing route to steadfast.net [208.100.33.123]
over a maximum of 30 hops:

  1     *        *        *     Request timed out.
  2     8 ms     8 ms     8 ms  ge-1-2-ur01.noblesville.in.indiana.comcast.net [
68.85.179.9]
  3    11 ms     8 ms     9 ms  pos-0-10-0-0-ar01.indianapolis.in.indiana.comcas
t.net [68.86.90.174]
  4    20 ms    20 ms    18 ms  pos-0-0-0-0-cr01.nashville.tn.ibone.comcast.net
[68.86.90.173]
  5    32 ms    26 ms    27 ms  pos-0-4-0-0-cr01.atlanta.ga.ibone.comcast.net [6
8.86.85.26]
  6    38 ms    34 ms    31 ms  pos-1-7-0-0-cr01.chicago.il.ibone.comcast.net [6
8.86.85.165]
  7    30 ms    33 ms    30 ms  68.86.89.194
  8    29 ms    30 ms    32 ms  ip17.208-100-32.static.steadfast.net [208.100.32
.17]
  9    30 ms    36 ms    38 ms  utility1.steadfast.net [208.100.33.123]

Trace complete.

Can anything be done to fix this?

[Justec]

you have a <40ms ping, I don't see what the problem is?

[Mike Bailey]

What specifically is odd about this? From what I can see, the routing is just fine. If you are experiencing actual trouble, please provide more information, and if possible, provide a sample traceroute that you ran prior to our comcast link being brought online.

[bg]

Can anything be done to fix this?

It's doing exactly what it's supposed to be doing. Good job, Steadfast!

[ManagerJosh]

Jake:

I'm not sure if there's anything Steadfast can do. The first 6 or so hops are within Comcast's own network.

[Ray]

Jake:

I'm not sure if there's anything Steadfast can do. The first 6 or so hops are within Comcast's own network.

Indeed. Steadfast can't control the incoming routes, other than advertising to specific carriers. That is entirely within Comcast's network. The only thing I could suggest would be to try contacting Comcast about it, as they would be the ones to control that route.

It is possible that they had a router or link problem causing the Indianapolis traffic to go through Atlanta, as I would think that Indianapolis would have a link straight to Chicago. However, sometimes, the most obvious path is not one that's available...

[Karl]

The only issue that seems to exist is that it seems Comcast is mis-labeling their RDNS, as there is absolutely no way that route would be able to make it from Atlanta to Chicago in 5ms or less as would be indicated by this:

5 33 ms 27 ms 27 ms pos-0-4-0-0-cr01.atlanta.ga.ibone.comcast.net [68.86.85.26]
6 34 ms 31 ms 32 ms pos-1-10-0-0-cr01.chicago.il.ibone.comcast.net [68.86.85.61]

On our outbound route it shows 23ms getting right to Noblesville, and then the added ~10ms would be from there to your house, which is about what can be expected out of most cable connections.

traceroute to 68.85.179.9 (68.85.179.9), 30 hops max, 38 byte packets
1 gw-shared (216.86.146.1) 0.416 ms 0.255 ms 0.233 ms
2 68.86.89.189 (68.86.89.189) 1.107 ms 0.956 ms 0.924 ms
3 pos-0-11-0-0-ar01.area4.il.chicago.comcast.net (68.86.90.50) 1.946 ms 1.494 ms 1.439 ms
4 68.85.177.50 (68.85.177.50) 23.949 ms 23.338 ms 23.219 ms
5 ge-1-2-ur01.noblesville.in.indiana.comcast.net (68.85.179.9) 23.072 ms 22.961 ms 23.058 ms
Trace complete.

[jake223]

I found a old traceroute from before the latency increase, it looks like the routing on comcast's network changed which caused the latency increase.

Before

Tracing route to ip88.208-100-14.static.steadfast.net [208.100.14.88]
over a maximum of 30 hops:

  1     *        *        *     Request timed out.
  2     7 ms     6 ms     7 ms  ge-1-2-ur01.noblesville.in.indiana.comcast.net [68.85.179.9]
  3     6 ms     8 ms     7 ms  pos-0-10-0-0-ar01.indianapolis.in.indiana.comcast.net [68.86.90.174]
  4     7 ms     6 ms     6 ms  pos-0-0-0-0-cr01.indianapolis.in.ibone.comcast.net [68.86.85.58]
  5    14 ms 	14 ms 	 13 ms  te-1-4-ar01.woburn.ma.boston.comcast.net [68.86.90.54]
  6    16 ms 	16 ms 	 15 ms  COMCAST-IP.edge1.Chicago2.Level3.net [4.71.248.30]
  7    14 ms 	21 ms 	 15 ms  xe-10-0-0.edge1.Chicago2.Level3.net [4.71.248.29]
  8    15 ms 	15 ms 	 19 ms  ae-21-56.car1.Chicago1.Level3.net [4.68.101.162]
  9    16 ms    22 ms    14 ms  WBS-CONNECT.car4.Chicago1.Level3.net [4.79.208.154]
 10    15 ms    14 ms    14 ms  ip61.216-86-149.static.steadfast.net [216.86.149.61]
 11    16 ms    15 ms    15 ms  ip88.208-100-14.static.steadfast.net [208.100.14.88]

i'm guessing that steadfast cant do anything about it?

[ManagerJosh]

Anything in the above traceroutes, that says steadfast.net we have control over. Anything else is that says Level3.net, Comcast.net, is generally beyond our control.

[Karl]

Yes, you can see that all of the difference is internal to Comcast's network. The issue is the route they're taking to Chicago, which is completely up to Comcast.