Cisco – Create Internal Connection Between ISR 4451 and EtherSwitch Submodule

ciscocisco-catalystcisco-commandscisco-ioscisco-isr

In a Cisco ISR 4451 we install a EtherSwitch 48 Port Module. The ISR is working and the EtherSwitch Module too. Now I want to create a route from ISR to EtherSwitch and read some Manuals and Forum threads how to do that.

The easy way is to plug a cable from ISR to EtherSwitch and the other Way is to create a BDI Interface on the ISR and Connect via VLAN to the Ethernet-Internal Port. But I cant create the config as shown in the forum Threads.

On Cisco ISR I should create this config:

interface Ethernet-Internal 1/0/0
  service instance 1 ethernet
    encapsulation dot1q 50
    rewrite ingress tag pop 1
  !
end

interface BDI 1
  ip address 10.0.0.1 255.255.255.0
end

Here is the config of my ISR 4451

Building configuration...

Current configuration : 146 bytes
!
interface Ethernet-Internal1/0/0
 no negotiation auto
 service instance 1 ethernet
  encapsulation dot1q 50
  rewrite ingress tag pop 1
 !
end

interface BDI1
 ip address 10.1.20.4 255.255.255.0
end

And this config is for the Catalyst Module:

Building configuration...

Current configuration : 154 bytes
!
interface GigabitEthernet0/52
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 50
 switchport mode trunk
 switchport protected
end
interface Vlan50
 ip address 10.1.20.3 255.255.255.0
end

But the BDI Interface is still down. What is wrong in my configuration? Any Ideas how to do that?

Best Answer

As per OP's comment, here's a copy of the post from oleg.bogdanov on Cisco support forums, which turned out to be a better solution.

This is strictly copy/paste from Cisco support forums and has not been made by me. It's only to give someone else a hint to a solution.

oleg.bogdanov wrote:

Note that my platform is a 4451 with a SM-X-ES3-24-P, but it should be the same in your case. The 4000 series supports SVIs as of recent code. You enable SVI support like this:

ethernet-internal subslot 1/0
platform switchport svi

Then you have to reboot and you can just trunk your VLANs to the switch module like you would on any layer 3 switch:

Vlan 11
name some_vlan

Vlan 13
name other_vlan

interface Vlan11
description some vlan
ip address 10.10.10.2 255.255.255.0
standby 1 ip 10.10.10.1
standby 1 priority 105
standby 1 preempt
no shut

interface Vlan13
description some other vlan
ip address 10.20.20.2 255.255.255.0
standby 1 ip 10.20.20.1
standby 1 priority 105
standby 1 preempt
no shut

interface Ethernet-Internal1/0/0
description Trunk to internal switch module
switchport mode trunk
switchport trunk allowed vlan 11, 13

Note that once you log into your switch module (the command has been changed to 'hw-module session 1/0') don't try to restrict the VLANs on the uplink port. Just allow them all else you get more stupid errors.

interface GigabitEthernet0/26
description Trunk to host router
switchport trunk encapsulation dot1q
switchport mode trunk
switchport protected

Vlan 11
name some_vlan

Vlan 13
name other_vlan

E.g.

Switch#sh int trunk

Port Mode Encapsulation Status Native vlan
Gi0/1 on 802.1q trunking 1
Gi0/26 on 802.1q trunking 1

Port Vlans allowed on trunk
Gi0/1 11,13
Gi0/26 1-4094

Port Vlans allowed and active in management domain
Gi0/1 11,13
Gi0/26 1,11,13

Port Vlans in spanning tree forwarding state and not pruned
Gi0/1 11,13
Gi0/26 1,11,13
Switch#

Hopefully this helps people save some time. Cisco has very poor documentation on proper configuration of these switch modules so I'm not surprised TAC gave the nonsense answer of "use an external cable".

Source:

https://supportforums.cisco.com/t5/lan-switching-and-routing/configuring-a-sm-x-layer-2-3-etherswitch-service-module-on-a/td-p/2660930

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