ESXI 5.1 - Losing access to management interface on vSwitch1 when vSwitch0 loses network access

I'm probably missing something obvious here, but, I am trying to make some adjustments to the Vkernel Port management interface on vSwitch0 that is set to VLAN ID: All (4095).

So I don't disconnect myself, I have added a second switch (vSwitch1), added the secondary NIC on my host to it and connected it to my switch.

I have connectivity to vSphere and via ping.

If I shut the port that connects vSwitch0 to my network infrastructure, my ping is maintained to my secondary vKernal Port, but I am unable to connect to vSphere...

Any tips greatly appreciated as always.

For a change to the management vSwitch's vlan settings, it's probably easier to just make the change with the console interface.

That being said, your problem with accessing management tools is probably this checkbox in the port group settings, which defaults to off:

Edit the port group to check that box and you should be able to connect the vSphere client against the secondary vmkernel port group.