Core switch Migration L3 Etherchannels?

[lowfell]

We are tasked with migrating a core network where 

Two Nexus 5596 currently terminate on a 6500

The 6500 is retiring and we are moving to a 9407r with two Supervisors.  the Two nexus will still be used.

I have been advised to use layer 3 etherchannels between the New 9407r & the Nexus.

Can someone tell me how these layer 3 links will propagate my vlan traffic? with an example config?

My understanding is the l3 etherchannel should look something like this

sw9407r#int port-channel 1
sw9407r#no switchport
sw9407r#ip address 10.1.1.1 255.255.255.0
sw9407r#exit
sw9407r#int range gi0/1-2
config-if-range#no switchport
config-if-range#channel-group 1 mode on
config-if-range#no shut
!
!
sw-nexus#int port-channel 1
nexus#no switchport
nexus#ip address 10.1.1.2 255.255.255.0
nexus#int range gi0/1-2
config-if-range#no switchport
config-if-range#no shut
#show etherchannel summary

[Jon Marshall]

L3 etherchannels are L3 links so they do not propagate vlan information. 

You would have different vlans/IP subnets on each set of switches and you would route between them. 

Jon

[lowfell]

So the etherchannel config in my post would be enough/suffice to apps all the traffic between the two switches is that correct?

[Jon Marshall]

It depends on what was setup before with the 6500. 

What were the connections before between the switches ? 

Jon

[lowfell]

I'll post a sanitised version of the original config once I have it. Sorry the core is a 4500 not a 6500 Thanks again for your help.

[Mark Malone]

Hi would you not use a VPC on nexus side then a standard PO back to the 4500 side , that would be a standard setup , the VPC is best on the Nexus side , i have this setup in multiple places and it works well between IOS nad NX-OS

[paul driver]

Hello

i assume you 4500 is the L3 for your lan estate and this new 9400 will be wanting to take on this role?

If so how are you planning migrate the L3 over to the new core - staged or all in one change?

depending on this will affect on how you go about Interconnecting the new core to the existing one 

[lowfell]

That’s correct. I’ll have access to the existing configs tomorrow, but basically, I was hoping to configure brand new connections from the NEW 9400 back to the Nexus using a Test Subnet, but using exact same vlan id’s so we can test all applications based on a copy of the existing 4500 config, transposed to the 9400. Once this has been tested as working, the idea on the night is to then readdress the 9400 with the real addresses, patch to the 9400 & switch the old 4500 off. At the moment, this is ALL THEORY & I’m looking for the best approach!
Many thanks,
L