xconnect with a local gateway from LAN

[sebastien3]

Hello,

I have two 891F routers connected with l2tpv3.

VLAN 1 is connected to a switch via the GE7 port of the router. I can ping any IP on subnet 10.0.0.1/24 in both directions ! Xconnect is UP and ready.

pseudowire-class XCONNECT
 encapsulation l2tpv3
 interworking ethernet
 protocol none
 ip local interface Loopback0
!
interface Vlan1
 no ip address
 xconnect A.B.C.D 1 encapsulation l2tpv3 manual pw-class XCONNECT
  l2tp id 2 1
!

 Now I can't create a local gateway for each router... For example on R1 I would like to have the IP 10.0.0.100/24 and on R2 10.0.0.200/24. This allows traffic to go out to the Internet on the local router and not on the remote router !

Bridge IRB or VRF can't work with interface Vlan1.

Have you an solution ?

Thanks !

[sebastien3]

1. Yes it is a real network !

2. Yes it works no problem. R1 Lo0 can ping R2 L0. The address in Lo0 is a routable public IP !

3. Yes it works except for the xconnect part. If I add a VLAN2 with ip nat inside+access-list I can go out to the WWW.

4. If but as already said the problem is not here...

I summarize the problem...

If I remove the xconnect configuration from vlan100 and delete BVI1 I go to the Internet without ANY problem.

int vlan100
ip address 10.0.1.200 255.255.255.0
ip nat inside

My problem is that with the xconnect configuration I need to have a local interface in order to be able to get the traffic out locally and not through the xconnect for the WWW.

xconnect is only used to extend the physical network between the two 891F routers.
The computers behind R1 will use the gateway 10.0.1.100 and those behind R2 10.0.1.200.

From a computer connected to R1 I can ping a computer behind R2. Same thing for R2 towards R1 !

How to create this gateway on R1/R2 ?

[Giuseppe Larosa]

Hello @sebastien3 ,

L2TPv3 provides a L2 point to point transport service and your SVI vlan 100 when configured with xconnect acts as the local connection point and it cannot have also a L3 configuration.

So a possible solution is to use a diffeent SVI

interface vlan 110

! configured with L3 desired configuration

ip address 10.0.1.200 255.255.255.0
ip nat inside

Then you connect a L2 physical port in vlan 110 with one port in vlan 100 with an external LAN cable.

I think this is what you can do with your devices.

IT is not elegant, but it should work (disabling CDP on the two connected interfaces may help to avoid useless log messages)

Hope to help

Giuseppe

[sebastien3]

Hello @Giuseppe Larosa 

---

L2TPv3 provides a L2 point to point transport service and your SVI vlan 100 when configured with xconnect acts as the local connection point and it cannot have also a L3 configuration.

I totally agree with that ! But I wanted to know if there was not a possibility to do it with a BVI interface more simply...

---

Then you connect a L2 physical port in vlan 110 with one port in vlan 100 with an external LAN cable.

Currently I use port F0 of the router with the xconnect configuration connected to it on a switch. I use another router port which is in vlan100 that I connect to the same switch.

All works I can use the xconnect to extend the LAN and use a local IP on each router

It would be the same to plug port F0 into another router port in VLAN 100

Thank you for the tip of the CDP I had not thought of it !

[MHM Cisco World]

link I share with you talk about this point, you can use two vlan, one which is use  to connect two router via xconnect and other for your local network but when I review this solution I dont see how we can extended the L2 via xconnect, we only simply routed the packet via other VLAN.

No physical ports will be associated with SVI (Interface VLAN). <<- this point in link I share talking about you can assign IP to SVI if it not physical connect.

[MHM Cisco World]

can I know more about connect two port to SW and one use for xconnect, can you please draw topology ?