Solved: Can we have the LAN interface on the cisco2811 router to be Layer2 interface

arulkumar80 · ‎05-20-2010

Hi,

I am using a cisco 2811 router.I am running short of Layer3 interface.

Can i use L2 interface on the router for connecting my LAN segment.

To explain in detail.

I have totally 4 L3interface on the router.

2 interfaces will be used for WAN connection

1 intercae will be used for internet connection

1 interface for HSRP

Now can i use the L2 interface for connecting my LAN segment and still have connectivity to 2WAN,Internet,HSRP

Please help

Regards

Arlkumar

Jonn cos · ‎05-20-2010

Yes you can do it. Consider HWIC-4ESW as a mini layer 3 switch with 4 ports. Now when you will add this card in ur 2811, you will see 4 L2 fastethernet ports. These ports are layer 2. So you need to create Interface Vlan 1 (SVI) and assign it your lan IP (which will serve as a gateway to your lan machines). Like this

Interface vlan 1

ip address 10.0.0.1 255.255.255.0

no shut

Now all the L2 ports of HWIC are part of vlan 1 and therefore part of this SVI.

Rate if helps

View solution in original post

glen.grant · ‎05-20-2010

Please clarify what you mean by a L2 interface . Do you have like a 4 port hwic module installed ? If so then yes you can run your lan on that as you can route thru that card by using configured SVI's .

arulkumar80 · ‎05-20-2010

Hi,

Can I assign ip address if I am using hwic-4esw.

Regards

Arulkumar

glen.grant · ‎05-20-2010

Yes you would create a layer 3 SVI and a Layer 2 definition in the vlan database and then put the port on the card into that vlan ...

Jonn cos · ‎05-20-2010

Yes you can do it. Consider HWIC-4ESW as a mini layer 3 switch with 4 ports. Now when you will add this card in ur 2811, you will see 4 L2 fastethernet ports. These ports are layer 2. So you need to create Interface Vlan 1 (SVI) and assign it your lan IP (which will serve as a gateway to your lan machines). Like this

Interface vlan 1

ip address 10.0.0.1 255.255.255.0

no shut

Now all the L2 ports of HWIC are part of vlan 1 and therefore part of this SVI.

Rate if helps

arulkumar80 · ‎05-20-2010

Thank you

chris.rae07 · ‎05-20-2010

Hi Arlkumar,

You can convert the swtich ports in an etherswitch module to Layer 3.

You can achieve this by the following commands-:

router(config)#int f0/1

router(config-int)#no switchport

router(config-int)#ip address ........

Hope this helps

Chris