[rbak-nsp] blackholing/null0

[Marcin Kuczera]

hello,

there is something strange in my SE100 (6.1.3.4).

I have established a blackholing system
below one example of a route received from route-server

[bgp1]RedBack_SE100#show ip route 65.98.34.210
     Longest match Routing entry for 65.98.34.210/32 is 65.98.34.210/32 
, version 18494605
     Route Uptime 00:14:01
     Paths: total 1, best path count 1

     Path information :

       Active path :
       Known via bgp 13000, type-External BGP, distance 170, metric 0,
       Tag 0, Originating AS # : 65444, Next-hop 192.0.2.1, NH-ID 0x31200001
[bgp1]RedBack_SE100#show bgp route 65.98.34.210
Address Family: ipv4 unicast
BGP table version is 30517058, local router ID is 91.195.159.133
Status codes: d damped, h history, > best, i internal
Origin codes: i - IGP, e - EGP, ? - incomplete

    Network            Next Hop                Metric  LocPrf  Weight Path
 >  65.98.34.210/32    192.0.2.1                    0     100     100 
65444 i
[bgp1]RedBack_SE100#

[bgp1]RedBack_SE100#show config | grep "ip route" | grep "null0" | grep 
"BlackHoling"
  ip route 192.0.2.1/32 null0 description BGP BlackHoling.pl

so, theoretically the traffic should get into null0.

But, it passes normally...


Look at this printout:
[bgp1]RedBack_SE100#show ip route 65.98.34.210 

     Longest match Routing entry for 65.98.34.210/32 is 65.98.34.210/32 
, version 18502191
     Route Uptime 00:05:51
     Paths: total 1, best path count 1

     Path information :

       Active path :
       Known via bgp 13000, type-External BGP, distance 170, metric 0,
       Tag 0, Originating AS # : 65444, Next-hop 192.0.2.1, NH-ID 0x31200001
[bgp1]RedBack_SE100#show ip route 65.98.34.211
     Longest match Routing entry for 65.98.34.211/32 is 65.98.0.0/17 , 
version 14735262
     Route Uptime 1w3d
     Paths: total 1, best path count 1

     Route has been downloaded to following slots
      02/0

     Path information :

       Active path :
       Known via bgp 13000, type-External BGP, distance 170, metric 0,
       Tag 0, Originating AS # : 25653, Next-hop 193.111.38.97, NH-ID 
0x345000A1, Adj ID: 0x10000B3, Interface vlan108
       Circuit 2/1:1023:63/1/2/4111


And, this second entry is the same as traceroute to 65.98.34.210:
stats:/etc/mrtg# traceroute 65.98.34.210
traceroute to 65.98.34.210 (65.98.34.210), 30 hops max, 40 byte packets
  1  r0-serv.leon.com.pl (195.66.73.1)  0.160 ms  0.139 ms  0.119 ms
  2  r0-to-bgp.leon.com.pl (195.66.73.253)  0.348 ms  0.328 ms  0.534 ms
  3  unused-37.38.111.193.atman.pl (193.111.38.37)  7.780 ms  7.854 ms 
7.840 ms
  4  195.81.208.45 (195.81.208.45)  29.326 ms  29.322 ms  29.316 ms
  5  ae1-0.ams-koo-score-2-re0.interoute.net (84.233.190.49)  36.408 ms 
  36.396 ms  36.364 ms
  6  ae0-0.ams-koo-score-1-re0.interoute.net (84.233.190.1)  36.397 ms 
36.931 ms  36.900 ms
  7  ams-ix.ae1.cr1.ams2.nl.nlayer.net (195.69.145.219)  36.919 ms 
36.879 ms  36.841 ms
  8  xe-2-2-0.cr1.iad1.us.nlayer.net (69.22.142.29)  154.019 ms  147.876 
ms  147.822 ms
  9  xe-3-0-0.cr1.nyc3.us.nlayer.net (69.22.142.74)  125.162 ms  124.787 
ms  124.769 ms
10  po1.ar2.nyc3.us.nlayer.net (69.31.95.154)  125.088 ms  125.308 ms 
125.366 ms
11  as25653.ge1-2.ar2.nyc3.us.nlayer.net (69.31.95.26)  127.128 ms 
127.057 ms  127.267 ms
12   (208.116.63.245)  127.533 ms  127.495 ms  127.590 ms
13  65.98.34.210 (65.98.34.210)  127.428 ms  127.358 ms  127.587 ms
stats:/etc/mrtg#



This system seems not to take under consideration the longest prefix 
match..., only the shorter one is taken.
Is it a BUG or some missconfiguration ??

Regards,
Marcin