VDS Health Check feature released in vSphere 5.1. A shadow port is created automatically for every uplink in your ESXi host and is used for transmitting and receiving health check related packets for each uplink. In ESXTOP, you can monitor the statistics for these shadow ports which can be used to debug/troubleshoot the network health check feature and this is why they are present.
One thing to note, these shadow ports are created regardless of whether or not your ESXi host is connected to a VDS or if you have the network health check features enabled. This is by design and there are four VMkernel modules that are responsible for the network health check feature:
After some investigation and testing in my lab, I found that I could unload the above VMkernel modules and the shadow vmnics entries would no longer appear in ESXTOP. To do this, you will need an ESXi 5.1 host which is not running any virtual machines and you will need to run the following commands in this exact order (as there are module dependencies):
vmkload_mod -u vlanmtucheckOnce you have successfully unloaded all four VMkernel modules, if you open up ESXTOP, you should no longer see the shadow vmnics. To restore the shadow vmnics, you can either reboot (since the unload is not persistent) OR you can run the following commands in this exact order:
vmkload_mod -u teamcheck
vmkload_mod -u heartbeat
vmkload_mod -u healthchk
vmkload_mod heartbeatNote: By loading the heartbeat VMkernel module, it also loads the healthchk module.