inter Vlan routing

julianov403 · ‎08-15-2017

Hello.

I'm having a doubt to configure in a Cisco 2800. The problem here is that there is a VLAN with I have to route between to network. The VLAN-id is 317. Let see a simple solution which I found in the internet.

Router#configure terminal
Router(config)# interface Gi0/0.317
Router(config-subif)# encapsulation dot1q 317
Router(config-subif)# ip address 10.252.234.46 255.255.255.252
Router(config-subif)# description VLAN 317 To Sub-Interface INTRAI2
Router(config-subif)# no shutdown
Router(config-subif)# exit

Router# configure terminal
Router(config)# interface Vlan317
Router(config-if)# ip address 212.XXX.XXX.XXX 255.255.255.248
ROuter(config-if)# description VLAN 317
Router(config-if)# no shutdown
Router(config-subif)# exit

This configuration is to make a forward from 10.252.234.46 to 212.XXX.XXX.XXX?

Georg Pauwen · ‎08-15-2017

Hello,

I am not clear on what you want to do. Are these two different routers ? Can you post a brief schematic drawing of what you want to accomplish ?

julianov403 · ‎08-15-2017

Hello Georg and thanks for the reply.

Well. The router's port Fa0/0 is connected to a iDirect modem and port Fa0/1 is connected to a cisco 2960. The switch is configure to have different vlans, thats because to it are connected differente equipment like addpad, ip phone, access point, etc. So for that its necessary to add thats vlans.

By the way, in the other side of the RF link there is a HUB and a router which it's connected to the core network and the ISP network. That side router has the same VLANs that the switch and a VRF.

So the router in the LAN, the 2800 has to manages the VLANs. For what I know the virutal interface and the vlan interface in the router has to have IP. What IP should I use? For example the virtual interface Gi0/0.317 has 10.252.234.46 and the vlan interface 212.xxx.xxx.xxx

Julio E. Moisa · ‎08-15-2017

Hi

So you have the vlan 317 (assuming you have a EWIC Card on the router for that Vlan) and you have the sub-interface 317 as well. Please feel free to correct me.

I have not implemented this situation but router will limit the broadcast domain so if the IP addressing is different you should not have any problem.

>> Marcar como útil o contestado, si la respuesta resolvió la duda, esto ayuda a futuras consultas de otros miembros de la comunidad. <<

Georg Pauwen · ‎08-16-2017

Hello,

you need a different subinterface for each VLAN that is configured on the switch and that you need to be routed on the router.

Post a schematic drawing of your setup so we can see what is connected to what...

Julio E. Moisa · ‎08-16-2017

are these networks connected to separate LANs, isolated devices?

>> Marcar como útil o contestado, si la respuesta resolvió la duda, esto ayuda a futuras consultas de otros miembros de la comunidad. <<

paul driver · ‎08-16-2017

Hello

In you OP you show Router# with a physical routed interface and a switch virtual interface? - Unless i am mistaken 2800 don't support SVI ?

As other have stated, either have the router per from the inter-vlan routing or theL3 switch(2960) but not both.

The router's port Fa0/0 is connected to a iDirect modem and port Fa0/1 is connected to a cisco 2960. The switch is configure to have different vlans,

So then the switch will perform the intervlan routing and fa0/1of the 2800 router will have a ip address assigned to it relating to one of these vlans

I am assuming you require Network Address Translation for your internal vlans, otherwise you have to either apply some static routes on the 2800 back towards your switch for connectivity.?

on the 2800:
212.xxx.xxx.xxx = Public ip address?
10.252.234.46 - vlan 317 ?

int fa0/0
ip address 212.xxx.xxx.xxx y.y.y.y.y
ip nat outside

int fa0/1
ip address 10.252.234.46 255.255.255.252 <----vlan 317
ip nat inside

access-list 10 permit 10.10.10.0 /24 <---- vlan 10
access-list 10 permit 11.11.11.0 /24 <---- vlan 11
access-list 10 permit 11.11.11.0 /24 <---- vlan 12
access-list 10 permit 10.252.234.44 /30 <---- vlan 317

ip nat inside source-list 10 interface fa0/0
ip route 0.0.0.0 0.0.0.0 fa0/0 x.x.x.x (isp next hop)

On the switch
ip routing

int vlan 10
ip address x.x.x.x y.y.y.y
int vlan 11
ip address x.x.x.x y.y.y.y
int vlan 12
ip address x.x.x.x y.y.y.y
int vlan 13
ip address x.x.x.x y.y.y.y
etc..

int vlan 317
ip address 10.252.234.45 255.255.255.252

vlan 10-13,317
exit

ip route 0.0.0.0 0.0.0.0 vlan 317 10.252.234.46

int x/x
description Link to 2800 router
switchport host
siwtchport access vlan 317

res
Paul

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Kind Regards
Paul