4221 Router + L2 Switching NIM (NIM-ES2-8) Basic Q

[navacc]

Hello,

I've been thrown this 4221 Router and NIM after not working with Cisco for a decade; I'm hoping this is a simple question.

I have multicast data going into Port 0/0/0 and I can confirm I can get the same data out of Port 0/0/1. My uncertainty lies with getting this same data out of of any of the Switching NIM ports (0/1/0 through 0/1/7).

If they were two separate pieces of equipment, I don't think I would have an issue, but as these are integrated I'm not sure how to tell the router to use the NIM. I did glance over documentation for it [https://www.cisco.com/c/en/us/td/docs/routers/access/interfaces/NIM/software/configuration/guide/4_8PortGENIM.html and I think question is too basic for even that.

Is it as simple as assigning an ip address to the Switch Port VLAN(s) and then implementing an ip route from 0/0/0? Or is there more to working with NIMs?

I don't have access to the equipment again until after the weekend to play around and I'm on limited time then, so I'm just attempting to go in more informed than I have been.

Thank you!

[Richard Burts]

Keep in mind that the ports of the NIM are essentially layer 2 switch ports. And remember that you can not configure layer 3 parameters (like IP addresses) on layer 2 ports. So you will need a vlan interface to configure an IP address and any other layer 3 things that you might need. As far as the 4221 is concerned the locally connected subnets can communicate. Not sure what kind of route for 0/0/0 you are mentioning. It is not clear what the 4221 will connect to and not clear whether the routing logic will be static routing or a dynamic routing protocol. The devices connected to ports on the NIM are just hosts on a connected subnet as far as the 4221 is concerned.

[navacc]

Thank you,

0/0/0 is connected to another router right now (also a 4221), as this is a test setup, which is feeding the incoming data to it. The multicast coming in is UDP. The switching ports off the NIM will connect out to hosts, all receiving this data. They should be static and I planned on treating the routing as such. I'm unfortunately in the dark myself to much more information than that about the host end.

I had given the ports VLANs and those VLANs ip addresses like you mentioned. I haven't gotten to having the data that is going into routing port 0/0/0 to come out of the switch ports.

I did try to have the VLAN(s) exist on the same subnet as 0/0/0 and ran into an overlapping subnet message. The router 'side' should be able to tell the data to traverse to another subnet, if I recall correctly, but I'm not sure how to tell it to do so with the NIM being internal.  If I had a separate router and switch, I'd essentially just set up the subnets and run the cable.

[Richard Burts]

By default the NIM layer 2 ports would be in vlan 1. In general it is better to put host ports info non default vlans, but to keep this simple and to make it easier to solve the issue raised in the original post I will suggest that you keep the ports in vlan 1. After things are working you might want to undertake changing the ports to a different vlan. 

In the original post you say that " I can get the same data out of Port 0/0/1" If you can get that data out of 0/0/1 then we should be able to get that data out on the NIM ports using these steps.

- select a subnet to use on the NIM vlan (as you have discovered it can not be the same as any subnet configured on any interface of the 4221.

- configure interface vlan 1

- configure on that vlan interface the IP address and mask to implement the subnet you selected for the vlan.

- configure the hosts connected to the NIM ports with IP addresses in that subnet, with the mask for that subnet, and with their gateway as the address you assigned for the vlan interface.

- if there were any other parameters on 0/0/1 that relate to the multicast data then configure similar parameters on the vlan 1 interface.

If the multicast data is going out 0/0/1 then it should also be going out the NIM interfaces.

[navacc]

Thank you, I will give it my best go with some trial and error.

Hoping it's just a matter of the subnets chosen. I don't think there's much multicast-related setup that I can do on the switch ports. I do already have the host ports off the default vlan, at least. 

I'll return and mark a solution on Monday.