6 Replies Latest reply: Nov 11, 2019 1:42 AM by Juergen Ilse CCNA R&S RSS

    SVI on a router?


      Hello all,


      Can we create SVI on a router?


      I saw this Youtube video and it has SVI on router R1. The guy didn't show how that was done though. So how is this done?








        • 1. Re: SVI on a router?



          Yes. A router with switch module. Example: Router 2901

          Check: https://community.cisco.com/t5/switching/ehwic-4esg-module-communication-with-external-networks/td-p/2726006



          • 2. Re: SVI on a router?

            Not on a traditional router no... VLAN's aren't defined in the same way as they are on switches.

            But as Ing_Percy says, routers can have extra modules installed that behave like switches.

            • 3. Re: SVI on a router?

              Luke and Percy,


              All the PBR examples that I come across on Youtube use a route-map to SET the desired next hop for the traffic. Besides this, is PBR used for anything else?


              Since PBR uses route-map, then can we use PBR to do the other SET functions of route-map?




              R4#show run inter g3/0

              Building configuration...

              Current configuration : 125 bytes


              interface GigabitEthernet3/0

              ip address

              ip policy route-map RM-7-TRAFFIC

              negotiation auto




              R4#conf t

              Enter configuration commands, one per line.  End with CNTL/Z.


              R4(config)#route-map RM permit



              Route Map configuration commands:

                continue     Continue on a different entry within the route-map

                default      Set a command to its defaults

                description  Route-map comment

                exit         Exit from route-map configuration mode

                help         Description of the interactive help system

                match        Match values from routing table

                no           Negate a command or set its defaults

                set          Set values in destination routing protocol


              R4(config-route-map)#set ?

                as-path           Prepend string for a BGP AS-path attribute

                automatic-tag     Automatically compute TAG value

                clns              OSI summary address

                comm-list         set BGP community list (for deletion)

                community         BGP community attribute

                dampening         Set BGP route flap dampening parameters

                default           Set default information

                extcomm-list      Set BGP/VPN extended community list (for deletion)

                extcommunity      BGP extended community attribute

                global            Set to global routing table

                interface         Output interface

                ip                IP specific information

                ipv6              IPv6 specific information

                level             Where to import route

                local-preference  BGP local preference path attribute

                metric            Metric value for destination routing protocol

                metric-type       Type of metric for destination routing protocol

                mpls-label        Set MPLS label for prefix

                origin            BGP origin code

                tag               Tag value for destination routing protocol

                traffic-index     BGP traffic classification number for accounting

                vrf               Define VRF name

                weight            BGP weight for routing table


              • 4. Re: SVI on a router?



                In CCIE, you can see about the "set" commands that operates with PBR


                Specifying the matching criteria for policy routing is relatively simple compared to defining the routing instructions using the set command. The route maps used by policy routing must match either based on referring to an ACL (numbered or named IPv4/IPv6 ACL, using the match ip address or match ipv6 address command) or based on packet length (using the match length command). To specify the routing instructions—in other words, where to forward the packet next—use the set command. Table 6-4 lists the set commands and provides some insight into their differences.

                Check the table in the link:

                CCIE Routing and Switching v5.0 Official Cert Guide Library - Narbik Kocharians, Peter Paluch - Google Libros


                In Cisco community




                • 5. Re: SVI on a router?

                  It can be used to set different metrics for routing protocols for Redistribution, local policy routing that you can set the IP next hop to null0, this can be used to drop local management traffic (in addition to MPP commands).


                  It can also be used to alter traffic CoS attributes, I forget what exactly off hand, but some routers don't understand certain types of tagging so PBR is used to change these values as well.


                  It's basically to manipulate traffic defined by its "source" rather than destination, and local policy routing is to manipulate traffic generated by the router in which you can't define an Ingress interface.


                  Good luck!

                  • 6. Re: SVI on a router?
                    Juergen Ilse CCNA R&S

                    Learner schrieb:


                    Hello all,


                    Can we create SVI on a router?

                    It depends. There are some routers with an integrated switch instead of Layer3 interfaces (Cisco886VA was such a router, on which you can't assign an IP address to the fastethernet interfaces, because those interfaces are switchports and you have to create VLAN interfaces to have L3 interfaces on that router). There are C7600 series Routers, which are something like C6500 switches in an other type of case (you can also create VLAN interfaces on this type of router).

                    But on most routers you may see in preparation of your studies (C1841, C1900 series, ...), is it not possible to configure a VLAN interface.