Just a few thoughts, try turning off ip.fastpath.enable.  (Verify you understand what that is doing before making any changes)  I have seen Nexus drop traffic as it traversed the vPC when fastpath enabled was on due to the unexpected source.  I do not recall the exact conditions when that occurred.

Also, probably not the case, but check your MTU as adding vlan tagging will add 4 bytes to your headers. 

interface xxxx

  description xxx-e0a

  switchport block unicast

  switchport block multicast

  switchport mode trunk

  switchport trunk allowed vlan xxxx

  spanning-tree port type edge trunk

  channel-group xxx mode active

From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Bob McKim
Sent: Tuesday, November 25, 2014 11:18 AM
To: Toasters
Subject: Need Working Nexus 7000 Config for cDOT - 2 scenarios

Hi toasters, I'm looking for a working Nexus 7000 config for the following 2 scenarios -

Single mode 10g ifgrp (2 interfaces) with 2 vlans
2 switch vPC for a two interface 10g ifgrp with 2 vlans

If we bring the single mode ifgrp (e0b and e0d) up with no vlan tagging, it works fine for each sub-net.  As soon as we add vlan tagging on cluster nodes, we can't ping the gateways.  Require the vlan tagging to support our failover groups.

This is what we tried on the Cisco for the single mode with 2 vlans - no dice.

config t
interface Ethernet1/14
description <<xxx>>
switchport mode trunk
switchport trunk native vlan 26
switchport trunk allowed vlan 26, 28
no shutdown

Thanks in advance,

Bob McKim
Senior IT Specialist
IBM Global Technology Services
NetApp Certified Professional

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