Prepend for nexthop NCS5500

[divadko]

Hi all,

can anyone helps me to find the best way to prepend traffic connected via one specific nexthop?

My platform is Cisco NCS 57c3 mod running on iosxr 7.10.2

My router is aggregating 2 peering centers. I have configured 1 neighbour for each peering center that acts as route server so i am receiving all prefixes from one neighbor but from specific nexhop.

I am receiving multiple prefixes as duplicates with same AS distances and 2-3 times per day the fraffic is flapping between this 2 peering centers. So i am thinking about to apply a policy rule that will prepent my AS 3 times for all prefixes learned via specific nexthop.

What is the best way to do it?

Make quite complex one rule that will also contain prepend my AS 3 times for specific nexthop and apply it for one neighbor? (i have applyed rule to filter my as and add community at the moment)

Is there any way to apply multiple route policy for one neighbour?

Or is there any way to apply policy for nexthop ip only?

thank you very much

br

dave

[MHM Cisco World]

You  can config two route-map one IN ans other OUT 

For filter your AS prefix the direction is IN 

For filter prefix from neighbor the direction is OUT

MHM

[divadko]

I think that platform doesnt support route maps. Only route-policy. I i can apply multiple route-policy on one neighbor???

[MHM Cisco World]

Same for ios xr' the rpl can apply IN or OUT under the neighbor (bgp)

The policy you use for advertise your AS prefix which direction?

MHM

[divadko]

To filter and advertise only my as for peers i am using rule for out direction.

[MHM Cisco World]

Sorry I make double review to your Q' and I want to clear point' your prefix need to prepend? How you prefix receive from server routers? 

Can you share topolgy?

MHM