Bad bad routing problems?

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1

We are seeing bad routing problems from outside our network. Can anyone
corroborate this or help?

We are on AS4276 and all traffic from us to our upstream seems good. Great
way to spend holiday weekend. /me wonders if anyone is even awake on the
NANOG list. :slight_smile:

2 addresses in our network I've tested with are:

216.223.200.14
and 216.223.192.68

Many many traces done, some interesting ones below:

Here is a succesful traceroute:
traceroute to 216.223.200.14 (216.223.200.14), 30 hops max, 40 byte
  1 <10 ms <10 ms <10 ms rt1.altair7.com [209.11.155.129]
  2 <10 ms 15 ms 16 ms 209.10.41.130
  3 <10 ms 16 ms 15 ms ge-6-1-0.core1.sjc1.globix.net [209.10.2.193]
  4 <10 ms 16 ms 16 ms so-4-2-0.core1.sjc4.globix.net [209.10.11.221]
  5 63 ms 46 ms 47 ms so-1-0-0.core2.cgx2.globix.net [209.10.10.150]
  6 62 ms 63 ms 47 ms so-0-0-0.core1.cgx2.globix.net [209.10.10.157]
  7 78 ms 94 ms 94 ms so-1-0-0.core2.nyc8.globix.net [209.10.10.162]
  8 78 ms 94 ms 94 ms pos15-0.core2.nyc1.globix.net [209.10.11.169]
  9 78 ms 94 ms 94 ms s5-0-peer1.nyc3.globix.net [209.10.12.18]
10 78 ms 94 ms 94 ms nyiix.peer.nac.net [198.32.160.20]
11 78 ms 94 ms 93 ms internetchannel.customer.nac.net [209.123.10.34]
12 78 ms 94 ms 94 ms auth-2.inch.com [216.223.200.14]

2

I don't recieve that route from any of our transit providers,
and the only place I found it was at LINX from AS8001

ldn2nxg1#sh ip bgp 216.223.192.68
BGP routing table entry for 216.223.192.0/19, version 0
Paths: (1 available, no best path)
  Not advertised to any peer
  8001 4276, (received-only)
    195.66.224.94 from 195.66.224.94 (209.123.12.62)
      Origin IGP, metric 50, localpref 100, valid, external
      Community: 8001:120 8001:4000 8001:4001 8001:10000,
      mpls labels in/out unknown/exp-null

Where we didn't accept it due to not being corect registered in the
IRR's - could it really be that filtering is now so effective, that one
loose global reachability if it's not ?

/Jesper

3

Strange, from my network I see you via GT and via Telus but not via AT&T

From me (as11647)
BGP routing table entry for 216.223.192.0/19
Paths: (2 available, best #2, table Default-IP-Routing-Table)
   Not advertised to any peer
   852 174 8001 4276
     209.115.141.1 from 209.115.141.1 (209.115.137.196)
       Origin IGP, localpref 100, valid, external
       Last update: Sat Aug 31 08:47:55 2002

   6539 8001 4276
     64.7.143.42 from 64.7.143.42 (64.7.143.42)
       Origin IGP, localpref 100, valid, internal, best
       Community: 6539:30
       Last update: Sat Aug 31 08:47:30 2002

From the AT&T CANADA routeserver (route-server.east.attcanada.com)
AT&T route server
route-server.east>show ip bgp 216.223.192.0/19
% Network not in table
route-server.east>

AT&T Canada gets to 8001 via Williams, but I dont see your /19 through them.

route-server.east>show ip bgp regex _8001_
BGP table version is 2266132, local router ID is 216.191.65.118
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete

    Network Next Hop Metric LocPrf Weight Path
*>i12.129.128.0/24 216.191.64.253 80 0 7911 8001 22420 i
*>i63.74.146.0/23 216.191.64.253 80 0 7911 8001 23368 i

4

I see 216.223.192.0/19 with these ASpaths:

wcg 7911 8001 4276
globix 4513 8001 4276
mfn 6461 8001 4276

and fail to see it (Network not in table)
behind AS2828 (XO) and AS1 (Genuity).

-mark

5

Hi,

FYI,

I'm currently sitting as customer to 5511, and I see your two mentioned
addresses behind AT&T (NY peering FT-AT&T), NAC.

mh

-----Message d'origine-----

6

Man it is hard to find where routes die when you are dead on the net.

2 hops out from our network was not broadcasting our routes. We should be
alive on the internet again to everyone. Thanks for the input as it helped
us find where our BGP broadcast died.

Gerald

7

Man it is hard to find where routes die when you are dead on the net.

tip - keep some access via another provider!