Nexus 5k upgrade to 9k

[eelco.driel]

Hi,

We're going to upgrade a core infrastructure at several locations (A, B and C). At each location 2 Nexus 5k are installed which are linked together via a VPC connection. The locations A and B are contain the same VLANs (streched VLANs) and location C can be accessed via routing. 

The 5k switches are going to be replaced by new 9k nexus switches which are also connected together via VPC. 

Is it possible to do a inplace upgrade of the switches? I mean can be shut down at one location the first 5k, move the configuration to a new 9k, connect the VPC connection and start the new 9k again.

In other words is it (temporary) possible to create a VPC connection between a 5k and a 9k nexus switch?

Regards,

Eelco

[Reza Sharifi]

Hi,

Creating a vPC between a 5k and a 9k should not be an issue.  The commands to configure vPC is the same for both platforms.

HTH

[Ajay Saini]

Hello,

The basic requirement for vpc peering is that hardware should be identical. If you wish to peer the devices in a vpc domain(even if temporary), it should not be possible between different chassis - in your case a 5k and 9k.

I doubt that the vpc will come up if you connect a 5k and 9k device, never tried that though. I am relying on my theoretical knowledge.

-

AJ

[dgalmarini]

How did this turn out for you? We will be doing the same upgrade for our DC core next year. Were you able to make all Nexus part of the same domain for easy link movement, or did you have to take a more strategic approach?

[j.a.m.e.s]

This is not quite the same scenario, but I just replaced a vpc pair of 9332-PQ with 9336c-FX2. It went fine except for one really confusing moment. At the point of closing down the old primary (a 9332-PQ) to trigger a failover to the new secondary (a 9336c-FX2), we left the old primary's peer KA link online (typically mgmt0). As a result of some loop prevention logic in vpc, the new 9336c-FX2 kept it's SVIs shutdown. In our case, the only SVI was an L3VNI (with no ip address) which caused the box to blackhole all the VXLAN traffic on our network.

The moral of the story is... if you're going to do an upgrade in this way, make sure you close down the peer KA as well as all the other links when it's time to do the initial failover to the new HW.