Connectivity Guide

Policy-based routing
PBR provides a mechanism to redirect IPv4 and IPv6 data packets based on the policies dened to override the switch’s forwarding
decisions based on the routing table.
Policy-based route-maps
A route-map is an ordered set of rules that controls the redistribution of IP routes into a protocol domain. When you enable PBR on an
interface, all IPv4 or IPv6 data packets process based on the policies that you dene in the route-maps. The rules dened in route-maps are
based on access control lists (ACLs) and next-hop addresses, and only apply to ACLs used in policy-based routing.
You can create a route-map that species the match criteria and resulting action if all the match clauses are met. After you create the
route-map, you can enable PBR for that route-map on a specic interface. Route-maps contain match and set statements that you can
mark as permit.
Access-list to match route-map
You can assign an IPv4 or IPv6 access-list to match a route-map. The IP access list contains the criteria to match the trac content based
on the header eld, such as the destination IP or source IP.
When permit or deny is present in the access-list, it is omitted and the action present in the route-map command is used for
policy-based routing. The permit keyword in the route-map statement indicates policy-based routing. The deny keyword in the route-
map statement indicates a switch-based forwarding decision, a PBR exception. Only use access list for the packet match criteria in policy-
based routing.
1 Assign an access-list to match the route-map in CONFIGURATION mode.
ip access-list access-list-name
2 Set the IP address to match the access-list in IP-ACL mode.
permit ip ip-address
Congure IPv4 access-list to match route-map
OS10(config)# ip access-list acl5
OS10(conf-ipv4-acl)# permit ip 10.10.10.0/24 any
Congure IPv6 access-list to match route-map
OS10(config)# ipv6 access-list acl8
OS10(conf-ipv6-acl)# permit ipv6 10::10 any
Set address to match route-map
You can set an IPv4 or IPv6 address to match a route-map.
1 Enter the IPv4 or IPv6 address to match and specify the access-list name in Route-Map mode.
match {ip | ipv6} address access-list-name
2 Set the next-hop IP address in Route-Map mode.
set {ip | ipv6} next-hop ip-address
Layer 3
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