Network interfaces work independently when one is disconnected, but do not work when both are connected

Products

• VMware vSphere ESXi

Issue/Introduction

Two or more ports are set up in a port channel for load balancing using EtherChannel or LACP.

The following behavior is observed:

• When at least one of these uplink ports is shut down administratively or disconnected, network traffic can flow from the ESXi host to the switch on the remaining connected port(s)
• When tested individually, not all uplink ports may allow network traffic to pass
• When all uplink ports are connected and enabled, network traffic does not pass

A status message or error similar to the following may be found on a Cisco® brand switch:

%ETC-5-CANNOT_BUNDLE2: Gi0/0/1 is not compatible with Gi0/0/2 and will be suspended


 

 

Cause

This behavior indicates a misconfiguration, software fault or hardware fault on the switch connected to the uplink.

CANNOT_BUNDLE2 indicates an issue with initializing EtherChannel on the switch.

Resolution

Contact your network hardware vendor for assistance with investigating and resolving this condition.