Cannot add an additional 'active' vmnic

Products

• VMware vSphere ESXi

Issue/Introduction

When adding a second 'active' vmnic to a VMkernel port, error is thrown:

An error occurred while communicating with the remote host.
Network configuration change disconnected the host from vCenter server and has been rolled back.

ThrowableProxy.cause
A change in the network configuration disconnected the host from vCenter Server. The change has been rolled back.

Cause

Misconfiguration of physical ports.

Resolution

With assistance from the network team, validate which physical port the vmnic is associated with. Check the configuration of the port. 

When using Virtual Switch Tagging (VST), a trunk port is necessary. When using External Switch Tagging (EST), an access port is necessary. 

If the incorrect port is used, connectivity will be broken until the vmnic is removed from 'active' status. 

Additional Information

For more information on VLAN tagging visit VLAN configuration on virtual switches, physical switches, and virtual machines