Nexus 5020 running NX-OS ver4.1(3)N2(1)

[Luke Akpor]

Hi Guys,

I am trying to configure double sided vPC from a pair of N5K (N5020 with NX-OS version 4.1(3)N2(1)) to a pair of Nexus 7K in a double sided or back-to-back vPC fashion.

For some reasons, whenever I complete the config and apply, everything seem fine and after 10mins or so one of the N5K falls apart, reboots and Bridge Assurance kicks in and starts blocking ports.

I have this same setup and configuration on some other locations which works fine.

The only difference is that the NX-OS version on the other sites is different from this particular site running 4.1(3)N2(1).

Can someone tell me if its not possible to run double-sided (back-to-back) vPC from the N5Ks to the N7Ks when running on this version 4.1(3)N2(1)  and the only solution is to upgrade to the latest code?

Thanks for any feedback.

[answanso]

Hi Luke,

AFAIK double-sided vPC has always been supported. I would look into upgrading to a more recent version of NX-OS, as that version is really old. I have a few customers right now running this same scenerio and I have moved them to 5.1 and 5.2 trains. If you want to send me your configurations I can take a look and see if I notice anything off, but I would imagine this will be resolved with an upgrade if you have the exact same setup working on a later version of NX-OS.

Thanks

Ant

[Luke Akpor]

Hi Ant,

Thanks for your feedback. I actually double checked and can see that the other site where the double-sided vPC work is running the same version of code of 4.1(3)N2(1).

I will look to upgrade this site though to the latest version. Is there anything I need to be aware of from moving from version 4.1(3)N2 to 5.2.1.N1.4? Can I upgrade direct or do I have to upgrade to a previous code before upgrading to the latest one?

Thanks

Luke

[answanso]

Hi Luke,

Unfortunately its not possible to directly upgrade. From looking into a bit here is an upgrade path option (there are others if you want to investigate):

4.1(3)N2(1) to 4.2(1)N1(1) - Disruptive Upgrade

4.2(1)N1(1) to 5.0(3)N1(1c) - ISSU

5.0(3)N1(1c) to 5.2(1)N1(4) - ISSU

Here is some documentation on upgrading:

http://www.cisco.com/en/US/partner/docs/switches/datacenter/nexus5000/sw/upgrade/521_N1_1/n5k_upgrade_downgrade_521.html

Some Caveats on ISSU:

- Cannot be STP root

- No L3 card, which the N5020 doesnt support anyway.

- No fast timers for LACP

HTH

Ant

[thomas.heins]

May I add this:

If you want to keep the downtime as little as possible, verify the master/slave state of your node regarding your FEX.

If you have a host dual homed on two FEXs and FEXs have the same master, you will experience a reboot of your FEXs at the same time.