Best Practice 2921 with SM-ES3G-24-P

[Derek Morin]

I understand that when you insert a service module into a 2921 that you need to configure a IP address to access the sm card.

My question, is the best practice to leave that interface that is created under the router and switch a Layer three 30 bit connection?  then just route the SVI's on the switch to the router?

or 

To trunk any networks across the interface that is created, with a bunch of encapsulated sub-interfaces?

Thanks

[Reza Sharifi]

To access the SM, you create an SVI with an IP address in your management vlan on the SM and than trunk the port between the SM and the router and create sub-interfaces on the router.

HTH

[Derek Morin · Accepted solution]

I opened at TACs and cisco instructed the following configuration.   The Gi1/0 created when you install the SM is your Layer 3 routed port to the switch and what you use when you session in.  We use a 30 bit ip on either side that is not included in the EIGRP.  The Gi1/1 is a trunk port used for traffic.  The SVI's are created on the ROUTER and then trunk'd across the gi1/1 for the client ports on the switch.

ROUTER#

!
!

interface GigabitEthernet1/0
 ip address 10.107.10.1 255.255.255.252
!
interface GigabitEthernet1/1
 description internal switch interface connected to Service Module
 switchport trunk native vlan 999
 switchport mode trunk
 no ip address
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan100
 ip address x.x.x.x 255.255.255.240
 ip helper-address x.x.x.x
!
interface Vlan200
 ip address x.x.x.x 255.255.255.192
 ip helper-address x.x.x.x

!

!

ROUTER# service-module gigabitEthernet 1/0 session 

SERVICE_MODULE#

!

!

interface GigabitEthernet0/51
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 999
 switchport mode trunk
!
interface GigabitEthernet0/52
 no switchport
 ip address 10.107.10.2 255.255.255.252