RE: BGP Filter

Auch... just reread my answer...

Just add the following to the route-map in order to get it to work...

Route-map FILTER permit 10
 Match as-path 90
Route-map FILTER deny 20
!
Ip as-path access-list 90 permit ^254$

So why is this needed? Well, default behaviour of a route-map is doing it
sequential until a match is made. With the original route-map non-comforming
routes didn't have anything to match. With my addition of sequence 20, you
have a "match any" sort of filter.

Regards,
Lars Christensen
CCIE #20292

-----Original Message-----
From: Lars Christensen [mailto:perseusdk_at_gmail.com]
Sent: 9. maj 2009 10:27
To: 'Cisco Fanatic'; ccielab_at_groupstudy.com
Subject: RE: BGP Filter

Your config should be working. However, did you remember to clear your
neighbour relationship after adding the new code?

Regards,
Lars Christensen
CCIE #20292

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Cisco Fanatic
Sent: 8. maj 2009 23:55
To: ccielab_at_groupstudy.com
Subject: BGP Filter

R4
++
!
router bgp 22
 no synchronization
 bgp log-neighbor-changes
 neighbor 10.10.50.1 remote-as 22
 neighbor 10.10.50.1 update-source Loopback0
 neighbor 10.10.60.1 remote-as 22
 neighbor 10.10.60.1 update-source Loopback0
 neighbor 22.22.252.254 remote-as 254
 no auto-summary
!

BB2
+++
!
router bgp 254
 no synchronization
 bgp log-neighbor-changes
 network 10.10.10.0 mask 255.255.255.0
 network 20.20.20.0 mask 255.255.255.0
 neighbor 22.22.251.254 remote-as 100
 neighbor 22.22.252.4 remote-as 22
 no auto-summary
!

R4#show ip bgp
BGP table version is 6, local router ID is 10.10.40.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network Next Hop Metric LocPrf Weight Path
*> 10.10.10.0/24 22.22.252.254 0 0 254 i
*> 20.20.20.0/24 22.22.252.254 0 0 254 i
*>i90.90.90.0/24 10.10.30.1 0 100 0 5022 6522 100 i
* i 10.10.30.1 0 100 0 5022 6522 100 i
*>i180.180.180.0/24 10.10.30.1 0 100 0 5022 6522 100 i
* i 10.10.30.1 0 100 0 5022 6522 100 i
*>i200.200.200.0 10.10.70.1 0 100 0 i
* i 10.10.70.1 0 100 0 i

Now, I want R4 to learn only those prefixes that originated in AS 254 from
BB2.

R4
++
!
router bgp 22
 neighbor 22.22.252.254 route-map FILTER in
!
route-map FILTER permit 10
 match as-path 90
!
ip as-path access-list 90 permit ^254$
!

But, I am not getting the desired result. Humm??

-Yuri
Received on Sat May 09 2009 - 10:42:01 ART