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New Member

Routing on a NM-16ESW module

I have a 3745 router that connects to remote branches via point to point T1s. I want to replace P2P with 10/100 Ethernet. 2 FE ports on board are being used. I want to add a NM-16ESW module to provide additional Ethernet connections.

My question is "can I configure each port on the NM-16ESW module as a routed port so that I can connect each remote site to the FE port on the switch module?" The way I read, I should be able to do this using SVI. Can anyone confirm this?

I greatly appreciate your response.

Thanks in advance.

H. Wilson.

  • WAN Routing and Switching

Re: Routing on a NM-16ESW module


The way I would do this is to configure a separate VLAN for each port (using 'switchport access vlan') and then configure a separate SVI (interface vlanx) for each VLAN e.g.

interface fast0/0/0

switchport access vlan 100

interface fast0/0/1

switchport access vlan 101

interface fast0/0/2

switchport access vlan 102

interface fast0/0/3

switchport access vlan 103


interface vlan100

ip address....

interface vlan101

ip address....

interface vlan102

ip address....

interface vlan103

ip address....

Hope that helps - pls rate posts that help.



New Member

Re: Routing on a NM-16ESW module

Thanks Paresh. One additional question. I am assuming that when I do this I need to add vlan subnets in my routing protocol. For example, let's say the vlan100 is in 172.100.x.x network and I use rip routing protocol. So I should have

router rip

network 172.100.x.x

Is it correct?

Thanks for your help in advance.



Re: Routing on a NM-16ESW module

Yes, you are very correct.


Re: Routing on a NM-16ESW module


That is absolutlely correct. Treat the VLAN interfaces as standard layer 3 interfaces ..therefore,just include their subnets within the network commands of all routing protocols that you wish to run.

Hope that helps - pls rate the post if it does.


Re: Routing on a NM-16ESW module


With newer IOS;es, you necessarily dont need to create vlans and then assign vlans to the ports and assign ip addresses to the vlan interfaces to get layer 3 routing on each port. You can do a "no switchport" directly under the fast E ports of the module and this command configures the switch port as a Layer 3 port. Take a look at this FAQ

You can also enable routing protocols on these ports, just like you do with other interfaces.


PS: Please remember to rate helpful replies!

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