Connecting N2Ks to N9Ks

[S891]

I am looking for some recommendations on connecting N2Ks to N9Ks. I do have following setup  and things in mind:

- dual N9K - 9508s in a VPC domain

- Dual 2232TM-E 

- No host VPCs will be setup 

- Each host will have dual connection to 2232 FEXs

I am looking for suggestion whether the approach I said is best and see what other options are available.I am interested in a setup that is most stable and tolerate upgrade with out much downtime. 

Thanks

[S891]

Anyone, please!

[Rick1776]

Sure I can help. What modules do you have in your 9508’s that will be uplinking the 2232 fex’s?

[Rick1776]

They are two ways to to connect the fex’s 

one is no port channel to the host and one port will be active the other standby and the second option  is creating a LACP port channel down to the host as in the option on the right side of the image. The second option both ports will be active and is the better design. This will also depend on if your host NIC and OS support LACP. Most likely it will.

You can can read more at the following link

https://www.cisco.com/c/en/us/products/collateral/switches/nexus-9000-series-switches/guide-c07-730115.html

The reason I asked about the modules in your 9500 is that not all modules support all FEXs.

Please see the following link for the comparability list. Also check the realese notes on your NX OS version as well.

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/hw/interoperability/fexmatrix/fextables.html

[S891]

Thanks for your reply. We have 9564PX line cards. We will not be using Port-channel on Hosts. My other question is how the FEXs should be connected to N9Ks. Should we have dual connection from each N2Ks to the N9Ks OR N2K-A should only connect to N9K-A? 

Any other important consideration for connectivity? 

[Rick1776]

Your last statement is correct N2K-A should only connect to N9K-A other than that you should be good to go. Just make sure you cingure the VPC in a certain order so you don’t run in to any issues.

I’ve done the following:
Enable the feature vpc and LACP
Create the VPC domain same on both sdies
Configure the keep-alive
Configure the peer-link
Then do a show vpc to make sure the basic vpc infrastructure is up
Last step is cresting the vpc member ports
Also make sure that the 9500’s are the root for your spanning-tree L2 vlans.



This is a pretty good guide.
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/6-x/interfaces/configuration/guide/b_Cisco_Nexus_9000_Series_NX-OS_Interfaces_Configuration_Guide/b_Cisco_Nexus_9000_Series_NX-OS_Interfaces_Configuration_Guide_chapter_0111.html#...

If you need assistance I work for a VAR that could help.

[S891]

Thanks again for your reply. I am  wondering what would be the advantage of 

a) Dual Homed Host (Active/Standby) and Active-Active FEX (VPC) Design      over the 

b) Dual-Homed Host (Active/Standby) and Single Homed FEX (Port Channel Mode) Design

Since both are supported on N9K. What benefits does b provide over a?

I am using this link as a reference:

https://www.cisco.com/c/en/us/support/docs/switches/nexus-2000-series-fabric-extenders/200363-nexus-2000-fabric-extenders-supported-un.html

 

[Rick1776]

Option b your more likley to have a device go down because of the single link as where with option a you’ll be covered in most disasters scenarios . Both are fine, you have to base it on your overall design with cost versus redundancy.