Nexus 5k/2K Upgrade Impact Dual NIC Servers

[Vishal Kolamkar]

Hi Team,

We have below topology of Nexus 5K & Nexus 2K dual homed to  5k1 & 5K2.

5k1---------------------5k2

    !                             !

    !--------fex200------!--------200/1/4----SERVER NIC1

    !--------fex 201-----!--------201/1/4-----SERVER NIC2

We have planned upgarde of Nexus 5K in VPC environement & we have doubt over the dual NIC servers being offline when Fex reboots.

Deatils as below
N5k1# show fex
  FEX         FEX           FEX                       FEX
Number    Description      State            Model            Serial
------------------------------------------------------------------------
201  *******                Online     **********   ******
202  *******                Online     *********    ******

N5k2# show fex

  FEX         FEX           FEX                       FEX

Number    Description      State            Model            Serial

------------------------------------------------------------------------

201  *******                Online     **********   ******
202  *******                Online     *********    ******

We have a DUAL nic server connected connected Eth 201/1/4 & Eth 201/1/4. During upgrade we are aware of Fex gets rebooted sequentially aftre image upgrade, we would like to know the impact/experience on below update

> FEX 200, Fex 201 reboots sequentially, Cisco doc says this but

> Will our Dual nic server loose connectivity, i mean is there a posiibilty both fex 200,202 go offline at the same time after image update & Server connected to these fex will loose its connectivity during upgrade or server will be online on one of the FEX?

There is no cisco document explaining such scenario, please provide confirmation on impact on such scenario

Regards,

Vishal

[kevin.dubourg1 · Accepted solution]

Hello,

I also checked this point recently, and i confirm there is no impact.

The upgrade is done sequentialy (in ISSU process of course, in disruptive mode all fex reboot at the same time) !

The extract of the RN:

"An ISSU first upgrades the switches. Once the switch is operational with the upgraded software, the FEXs are upgraded. This upgrade of the FEX is done in a rolling fashion - one FEX at a time. Note that this upgrade on the Fabric Extenders is non-disruptive, similar to the upgrade of the switch."

If your server is connected with a failover mode, it's not disruptive ! There is approximately 30 secondes in my experience between fex upgrade. 

You can proceed with trust ^^ (i checked this point with Cisco support team and from my experience). Just follow the upgrade path and the ISSU process.

Enjoy !