Nexus "Clustering"

[tobin_jim]

I'm working on a project that will at some point be using 2 x 5020 Nexus switches and 12 x 2248s. I've never worked with the platform before. The 5020s will be connected together and the 2248s dual homed to the 5020s. Is it possible to cluster the switches to act as one large stack? I can't seem to find any reference or config guides for this config on the Cisco site. Any help would be appreciated.

[Darren Ramsey · Accepted solution]

What you are looking for is vPC, and in 5.0 there is the config-sync feature to synchronize parts of the configuration between the two 5020.

Configuration Synchronization

Q. What is the configuration synchronization feature introduced in Cisco NX-OS Release 5.0(2)N1(1) for the Cisco Nexus 5000 Series?

A. Configuration synchronization (config-sync), when enabled, allows the configuration made on one switch to be pushed to another switch through software. The feature is mainly used in virtual PortChannel (vPC) scenarios to eliminate the manual configuration on both vPC peer switches. It also eliminates the possibility of human error and helps ensure that both switches have the exact same configuration.

Q. Does config-sync require special hardware?

A. Config-sync is a software feature that is hardware independent. Starting with Cisco NX-OS Release 5.0(2)N1(1), it is supported on all Cisco Nexus 5000 Series Switches, including the Cisco Nexus 5548P.

Q. Can Type 1 and Type 2 inconsistencies be avoided with config-sync?

A. No. vPC and config-sync are two separate features. For vPC to be operational, Type 1 and Type 2 parameters must match. If the parameters do not match, users will continue to experience a vPC-failure scenario. Config-sync allows the user to make changes on one switch and synchronize the configuration with that on the other peer automatically. It saves the user from having to create identical configurations on each switch.

[Ozden Karakok · Accepted solution]

Hi Tobin,

You will need to use/configure Virtual PortChannel(vPC) on the Nexus 5020s (instead of clustering).

It is similar to Cisco Catalyst 6500 Virtual Switching System (VSS). With regard to Cisco EtherChannel technology, the term “multichassis EtherChannel (MCEC)” refers to either technology interchangeably.

You may want to read below design guide for the big picture (if you want to see the available topologies  with N5K and N2K please directly go to page 10)

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9670/C07-572831-00_Dsgn_Nexus_vPC_DG.pdf

And for the practical details, I believe below one would be better: (5K/2K topologies are in page 4)

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9670/design_guide_c07-625857.pdf

I hope this answers your question.

Thanks,

Ozden

[tobin_jim]

Thank you both. That's given me a great starting point to learn from.