Sometimes when third party plugins or solutions work with vCenter and ESXi (Like NSX) they will create a custom
TCP/IP stack for them to use.
If for whatever reason (say, unclean uninstall) you need to remove the
TCP/IP stack you can’t do it from the vCenter GUI, log into each host directly and execute:
esxcli network ip netstack delete -N="stack_name"
E.g. if you are uninstalling
NSX and get a stuck
esxcli network ip netstack remove -N="vxlan"