adding multiple route-maps on bgp nei

[mohAmed khAdr]

All,

I am trying to combine both AS_Prepend & AS_filter-list on the same neighbor.

I am using continue for route-map config

It ain't working.

Pls see attached.

What am missing?

Thx

mohamed 

[Georg Pauwen]

Hello,

your neighbor is in AS 200. You are prepending the as path with 200. As soon as the neighbor sees its own AS in the path, it will not even install the route in the BGP database.

Try the below to see the difference (for simplicity I matches with a prefix list that allows all routes):

ip prefix-list ALL_ROUTES seq 5 permit 0.0.0.0/0 ge 1
!
route-map AS_Prep permit 10
match ip address prefix-list ALL_ROUTES
set as-path prepend 100 100 100

R2_AS_200#sh ip bgp
Network Next Hop Metric LocPrf Weight Path
*> 10.10.10.2/32 192.168.2.2 0 0 35000 100 100 100 i
* 192.168.2.0 192.168.2.2 0 0 35000 100 100 100 i

[Vinit Jain]

HI Mohamed

It is not clear from the config or topology, what prefixes are you advertising towards AS 200. Could you please share the below info:

- topology

- show ip bgp     // from the router where you are performing AS prepend

- show ip bgp nei 192.168.2.1 advertised-routes

[mohAmed khAdr]

VJ

Pls see attached.

Take @ look @ route-map conf. Did I get it rite? I used key word "continue" to have multiple route-maps ( as perpend, as-path filter list, MED, etc) under 1 name AS_Perp

I still don't see nei showing as-prepend.

My Q is; can you config/add multiple route-maps on(filters) on a neighbor? 

Thx

mohamed

[mohAmed khAdr]

VJ,

neither as-path filter list, nor as-perpend is working as I can see router 1 prefixes on router 2and visa versa,

Thx

mohamed

[Vinit Jain · Accepted solution]

Hi Mohamed

thanks for the info. I see the below problem here:

neighbor 192.168.2.1 route-map AS_Prep out  <<<<<<<<

R3_Core_AS_300(config)#route-map AS_Prepend perm 10  <<<<<<< different Route-map name
R3_Core_AS_300(config-route-map)#set as-path prepend 300 300 300 300 300
R3_Core_AS_300(config-route-map)#con
R3_Core_AS_300(config-route-map)#route-map AS_Prep perm 20  <<<<< Same route-map name
R3_Core_AS_300(config-route-map)#match as-path 1
R3_Core_AS_300(config-route-map)#exit

You can only apply one route-map to a neighbor in a particular direction. Here you are using two different route-maps. You can try using the same route-map name per different permit / deny sequences.

Please modify your route-map and let me know how it goes.

Hope this clarifies your doubt.

[mohAmed khAdr]

VJ,

Oh, the **bleep** typo.

You good sharp eyes pal.

Now it's working

Thx much

Best

mohamed

[Georg Pauwen]

Hello,

I am lost. In your original post you sent AS Path prepends of 200 to neighoring AS 200, which causes the neighboring router to drop the routes.

route-map AS_Prep permit 10
set as-path prepend 200 200 200
continue
!
route-map AS_Prep permit 20
match as-path 1
!
router bg 35000
neighbor 192.168.2.1 remote-as 200
neighbor 192.168.2.1 ebgp-multihop 255
neighbor 192.168.2.1 route-map AS_Prep out

I haven't followed the entire thread, but how did you get this resolved ?

[mohAmed khAdr]

I corrected the route-map to 300 300 300.
It was typo and Sunday slacking!