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Cisco NM module/functionality/compatability

Hello all,

I feel a slight bit intimidated by posting here with a question that may sound a bit unsual, especially given the fact that most of the people here have much superior knowledge than I do.

Here is my question.

I have a 3745 router.

I want to add the functionality of gigabit ethernet to the router.

I have a NM-ESW-16  16 port expansion module in the router now.

I have ordered the GE-DCARD-ESW daughterboard for the NM-ESW-16 that gives the NM-ESW-16 module 1 gigabit port.

I also have a 3750G gigabit switch.  The router is set up as a Router-on-a-stick configuration with VLAN/Sub interface configurations.

I am wondering if the GE-DCARD-ESW will allow for a gigabit connection to the gigabit 3750 switch so that I may be able to have gigabit data transfer speeds to the router so that routing to the sub interfaces may take place faster.  I guess I am trying to say that I would like to be able to eleminate the 100MB/s bottleneck in my network.  I read somewhere that milticast and a few other features were not supported on router ios versions 15.x and up.  Luckly everything I have router wise is running on 12.4.

I hope that someone can aswer this question, and I am guessing that I would remove the current cat5 cable from my int0/1 that goes to the switch and place that cable into the new gig port and configure that interface as I have my old int0/1 configured with all the vlan/sub interface confgurations and then shut the int 0/1interface as I would no longer be using it.  am I right?

This is a home cisco lab that I have been working on for quite a while.  I am just trying to see what kind of limitations are out there and in the future be able to offer different solutions to people that may be looking for future upgrades.

Everyone's tags (3)

Re: Cisco NM module/functionality/compatability


It looks like if you are running at least IOS 12.2.15 you could now use the ESW port as a routed port However the bad news is that it does not support sub-interfaces

Routed Ports

A routed port is a physical port that acts like a port on a router; it does not have to be connected to a router. A routed port is not associated with a particular VLAN, as is an access port. A routed port behaves like a regular router interface, except that it does not support subinterfaces. Routed ports can be configured with a Layer 3 routing protocol.

You have 2 options.

1)Config your ESW port as a 802.1Q trunk

Create SVI interfaces for each of your VLANS very similar to 3750 config.

2) Instead of LAYER 2 use a LAYER 3 Routd port at both the 3745 (ESW PORT) and the same on your 3750

interface /x/x/x

no switchport

ip address a.b.c.d m.m.m.m

Change you thinking and IP route all the traffic btween the router and switch



Please rate useful posts

Regards, Alex. Please rate useful posts.