It is possible in BGP?

Unanswered Question
May 8th, 2012


In my location we have one cisco 1841 router with two ISP(BSNL&Tulip) is connected.

  Both links are mpls and configured in BGP protocol.

  LAN IP :

  WAN IP : Link)

   WAN IP : Link)

   Now all systems are working through Tulip link.there is one DVR connectivity and we configured one IP is

   My Requirement:

   We want all traffic should go to Tulip Link and DVR traffic should go to BSNL link only.

    In my HO router i given reverse traffic for DVR to BSNL link.

    My configuration:

interface FastEthernet0/0

description ***** Branch-LAN *****$ETH-LAN$

ip address

duplex auto

speed auto

keepalive 1000


interface FastEthernet0/1

description $$TULIP-WAN$$

bandwidth 512

ip address

ip accounting output-packets

duplex auto

speed auto


interface BRI0/0/0

no ip address

encapsulation hdlc


isdn switch-type basic-net3

isdn point-to-point-setup


interface Serial0/1/0

description #### BSNL WAN 2MBPS ####

ip address

ip accounting output-packets

ip nbar protocol-discovery

ip flow ingress

ip flow egress

ip virtual-reassembly

encapsulation ppp

load-interval 30

no fair-queue


router bgp 68001

no synchronization

bgp log-neighbor-changes

network mask

neighbor remote-as 65500

neighbor description ***TULIP WAN***

neighbor soft-reconfiguration inbound

neighbor remote-as 9829

neighbor soft-reconfiguration inbound

no auto-summary

  it is possible in BGP??

  If possible means kindly tell me how to configure??

I have this problem too.
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Sergey Fer Tue, 05/08/2012 - 22:30

You need to advertise your more specific DVR route to BSNL and not advertise it to Tulip. It is for traffic incoming to your DVR location. Another direction must be controlled by PBR for example. Or you may use OER/PfR.

Sergey Fer Wed, 05/09/2012 - 03:58

I'll try.

First of all you need to create static IP route for your DVR like this:

ip route Fa0/0

We need it to be in BGP table to advertise.

Next. Add network statement into BGP.

router bgp 68001

     network mask

Then you need to filter this network out of advertising to Tulip.

ip prefix-list DVR

route-map TO_TULIP deny 10

     match ip address prefix DVR

route-map TO_TULIP permit 20

router bgp 68001

     neighbor route-map TO_TULIP out

And softly reset Tulip session (like clear ip bgp * out). Now your DVR is announced through BSNL but not through Tulip. Your HO router will get routes and choose the most specific one (/32), which comes from BSNL.

Next stage. You need to send DVR's traffic to BSNL.

ip access-list standard DVR

     permit host

route-map PBR

     match ip access-group DVR

     set ip next-hop

interface Fa0/0

     ip policy route-map PBR

Now your DVR's traffic will come to BSNL. Hope this helps and hope I didn't forget something importaint.


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