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cisco 4900 layer 3 routing priority

I have a peculiar secnario with a set of routes on a cisco 4948 layer 3 switch (core switch(

examples are:

172.16.x.x is my main network

I have a static route:

ip route 172.16.0.0/17 to an upstream route 172.16.1.1
Iip route 172.16.2.0/24 to another router 172.16.2.1

the problem is that traffic is constantly routing to the 172.16.1.1 router due to it matching the first ip route, however i want specific traffic for 172.16.2.0/24 to route to another route, I cannot remove or change the existing /17 route, is there any way to set route priority so that traffic will first hit the 172.16.2.0/24 route instead of the first 172.16.0.0/17 route or am I stuck?

ddiazp

You need to set up route-maps for your scenario:

1. create access-list to match the traffic you want to set the route for

2. create route maps and apply that access-list:

route-map <NAME> permit
match ip <access-list name>
set ip next-hop <gateway>

done

pathix

ASKER

SO would route maps take precedence over the routing table itself? would i create a route map for just 172.16.2.0/24,

or create a route map with the entire routing table in it and remove all static routes? how does this affect directly connected routes?

ASKER CERTIFIED SOLUTION

Sanjeevloke

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ipajones

I agree with @sanjeevloke in that when a route for a destination IP is determined from the routing table the longest prefix length matching subnet will be used. So any traffic with a destintation of 172.16.2.x should always use 172.16.2.1 as the next hop. Are you using any routing protocols and is the default AD of 1 assigned to these static routes ?
--IJ

domenicosilletti

I agree, the more specific route has the precedence, please post the sh ip route 172.16.2.0 to solve the mystery