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BGP + Route map + Next Hop

Hi,

I created these routers with below configuration

R1===================R2

R1 connected to R2 with DTE-DCE serial.

hostname R1 ! interface Loopback0 ip address 131.108.1.1 255.255.255.0 ip policy route-map FROM-131.108.1.1-TO-131.108.3.1 ! interface Loopback1 ip address 131.108.4.1 255.255.255.0 ip policy route-map FROM-131.108.4.1-TO-131.108.6.1 ! interface Serial0 ip address 131.108.2.1 255.255.255.252 no fair-queue ! interface Serial1 ip address 131.108.5.1 255.255.255.252 clockrate 56000 ! router bgp 1 bgp log-neighbor-changes network 131.108.1.0 mask 255.255.255.0 network 131.108.4.0 mask 255.255.255.0 neighbor 131.108.2.2 remote-as 2 neighbor 131.108.5.2 remote-as 2 ! access-list 100 permit icmp host 131.108.1.1 host 131.108.3.1 access-list 101 permit icmp host 131.108.4.1 host 131.108.6.1 route-map FROM-131.108.1.1-TO-131.108.3.1 permit 10 match ip address 100 set ip next-hop 131.108.2.2 ! route-map FROM-131.108.4.1-TO-131.108.6.1 permit 10 match ip address 101 set ip next-hop 131.108.5.2

=========================

hostname R2 ! interface Loopback0 ip address 131.108.3.1 255.255.255.0 ! interface Loopback1 ip address 131.108.6.1 255.255.255.0 ! interface Serial0 ip address 131.108.2.2 255.255.255.252 no fair-queue clockrate 56000 ! interface Serial1 ip address 131.108.5.2 255.255.255.252 ! router bgp 2 bgp log-neighbor-changes network 131.108.3.0 mask 255.255.255.0 network 131.108.6.0 mask 255.255.255.0 neighbor 131.108.2.1 remote-as 1 neighbor 131.108.5.1 remote-as 1

=============================

R1#sh ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

131.108.0.0/16 is variably subnetted, 6 subnets, 2 masks B 131.108.6.0/24 [20/0] via 131.108.2.2, 00:28:55 C 131.108.5.0/30 is directly connected, Serial1 C 131.108.4.0/24 is directly connected, Loopback1 B 131.108.3.0/24 [20/0] via 131.108.2.2, 00:28:55 C 131.108.2.0/30 is directly connected, Serial0 C 131.108.1.0/24 is directly connected, Loopback0 R1#sh ip bgp BGP table version is 5, local router ID is 131.108.4.1 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

*> 131.108.1.0/24 0.0.0.0 0 32768 i
  • 131.108.3.0/24 131.108.5.2 0 0 2 i
*> 131.108.2.2 0 0 2 i *> 131.108.4.0/24 0.0.0.0 0 32768 i
  • 131.108.6.0/24 131.108.5.2 0 0 2 i
*> 131.108.2.2 0 0 2 i

========================================================

When I tried to ping from 131.108.4.1 to 131.108.6.1, the route-map didn't pickup anything.

R1#debug ip policy Policy routing debugging is on R1#ping Protocol [ip]: Target IP address: 131.108.6.1 Repeat count [5]: Datagram size [100]: Timeout in seconds [2]: Extended commands [n]: y Source address or interface: 131.108.4.1 Type of service [0]: Set DF bit in IP header? [no]: Validate reply data? [no]: Data pattern [0xABCD]: Loose, Strict, Record, Timestamp, Verbose[none]: Sweep range of sizes [n]: Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 131.108.6.1, timeout is 2 seconds: Packet sent with a source address of 131.108.4.1 !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 36/36/40 ms R1#u all R1#debug ip packet IP packet debugging is on R1#ping Protocol [ip]: Target IP address: 131.108.6.1 Repeat count [5]: Datagram size [100]: Timeout in seconds [2]: Extended commands [n]: y Source address or interface: 131.108.4.1 Type of service [0]: Set DF bit in IP header? [no]: Validate reply data? [no]: Data pattern [0xABCD]: Loose, Strict, Record, Timestamp, Verbose[none]: Sweep range of sizes [n]: Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 131.108.6.1, timeout is 2 seconds: Packet sent with a source address of 131.108.4.1 !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 52/73/124 ms R1#

00:40:46: IP: tableid=0, s=131.108.4.1 (local), d=131.108.6.1 (Serial0), routed via RIB 00:40:46: IP: s=131.108.4.1 (local), d=131.108.6.1 (Serial0), len 100, sending 00:40:46: IP: tableid=0, s=131.108.6.1 (Serial0), d=131.108.4.1 (Loopback1), routed via RIB 00:40:46: IP: s=131.108.6.1 (Serial0), d=131.108.4.1, len 100, rcvd 4 00:40:46: IP: tableid=0, s=131.108.4.1 (local), d=131.108.6.1 (Serial0), routed via RIB 00:40:46: IP: s=131.108.4.1 (local), d=131.108.6.1 (Serial0), len 100, sending 00:40:46: IP: tableid=0, s=131.108.6.1 (Serial0), d=131.108.4.1 (Loopback1), routed via RIB 00:40:46: IP: s=131.108.6.1 (Serial0), d=131.108.4.1, len 100, rcvd 4 00:40:46: IP: tableid=0, s=131.108.4.1 (local), d=131.108.6.1 (Serial0), routed via RIB 00:40:46: IP: s=131.108.4.1 (local), d=131.108.6.1 (Serial0), len 100, sending 00:40:46: IP: tableid=0, s=131.108.6.1 (Serial0), d=131.108.4.1 (Loopback1), routed via RIB 00:40:46: IP: s=131.108.6.1 (Serial0), d=131.108.4.1, len 100, rcvd 4 00:40:46: IP: tableid=0, s=131.108.4.1 (local), d=131.108.6.1 (Serial0), routed via RIB 00:40:46: IP: s=131.108.4.1 (local), d=131.108.6.1 (Serial0), len 100, sending 00:40:46: IP: tableid=0, s=131.108.6.1 (Serial0), d=131.108.4.1 (Loopback1), routed via RIB 00:40:46: IP: s=131.108.6.1 (Serial0), d=131.108.4.1, len 100, rcvd 4 00:40:46: IP: tableid=0, s=131.108.4.1 (local), d=131.108.6.1 (Serial0), routed via RIB 00:40:46: IP: s=131.108.4.1 (local), d=131.108.6.1 (Serial0), len 100, sending 00:40:46: IP: tableid=0, s=131.108.6.1 (Serial0), d=131.108.4.1 (Loopback1), routed via RIB 00:40:46: IP: s=131.108.6.1 (Serial0), d=131.108.4.1, len 100, rcvd 4

==================================

What I want were:

any ICMP from 131.108.1.1 to 131.108.3.1 will be delivered using route

131.108.1.1-131.108.2.1-131.108.2.2-131.108.3.1

any ICMP from 131.108.4.1 to 131.108.6.1 will be delivered using route

131.108.4.1-131.108.5.1-131.108.5.2-131.108.6.1

  1. Where was the wrong part of configuration?

  1. Why?
  2. How can I fix it?
Reply to
David Sudjiman
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David,

I didn't look over your config carefully, but I'm not sure that route maps will work when applied to the loopback interface. I have always applied them to the incoming physical interface.

Regards, Steve

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Reply to
Steve

Hi,

I'm not sure either; if loopback traffic is considered "local" then you could use "ip local policy route-map " to policy route locally generated traffic.

Regards, Gabriele

"Steve" ha scritto nel messaggio news:QbydnYEu5KSbtTPYnZ2dnUVZ snipped-for-privacy@comcast.com...

Reply to
Gabriele Beltrame

Not sure if the above suggestion for "local" policy will do the trick, but the following will: Put a PC on the ethernet port of your router, and place the policy map on the ethernet. Ping from your PC.....

Reply to
John Agosta

Thx to Steve, Gabriele, and John.

I thought that was the problem, couldn't be simpler :-)

Let me try that and let you guys know.

Reply to
David Sudjiman

Well, I tried by using e0 and put my laptop. The icmp packet goes to the destined network but not going through the path I want.

However, one thing that confuse me. It worked using "ip local policy". Can somebody explain to me why I can't using per interface ip policy?

Reply to
David Sudjiman

Assuming the route map was re-written correctly to reflect what was happening at the new location (e0), I don't see why having your PBR statement on the inbound interface wouldn't have worked.....

Reply to
John Agosta

I've created a diagram and several info if you keen to help

I have two routers that connected back-to-back using two serials. I also have each e0 on each router (R1 and R2) configured. both routers are using BGP AS 1 and BGP as 2, respectively. What I?m trying to do next is to make any ICMP packets from R1?s e0 going to path R1E0-R1S1-R2S1-R2E0. I?m using route-map and next hop to achieve this.

The problem is why can?t I use ip policy route-map on the interface yet I have to use ip LOCAL policy route-map to do this?

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Reply to
David Sudjiman

Case closed. Explanation on

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Reply to
David Sudjiman

Hi,

Policy routing applied to an interface is only taken in consideration for traffic entering that interface and not for locally generated traffic ( for locally generated traffic you use ip local policy )

Your ping trest from the Windows box connected to e0/0 probably failed due to an error in route-map ( e.g access-list 100 permit icmp host 20.20.20.1 host 10.10.10.1 )

Try something like this: Applying that route map to either e0/0 and as "local policy" should give you a consistent result

Reply to
Gabriele Beltrame

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