Issue explanation:

I went to prepare a cluster but the hosts never fully installed.
I figured I'd uninstall and give it another try.
Now all the hosts in the cluster report "In Progress" with the cluster status "Uninstalling".
I've rebooted all hosts multiple times and checked that the VIBs have been removed.

esxcli software vib list
esx-vxlan
esx-vsip
esx-dvfilter-switch-security

The manager and controllers have been rebooted as well.

 

Solution:

The vibs had already been uninstalled but the task was still hung.
I was able to work around this issue by disconnecting each host and adding back to a different cluster.
I deleted the cluster that was stuck and was then able to prepare the hosts in a new cluster.
The only think I lost was VM folder structure.
The hosts installed without issue and have now been added into my transport zone.

Note:

1. Do not forget to have DNS server and add there:

  • vCenter
  • esxi's
  • NSX Manager
  • Controllers

2. Domain Controller is not compulsory but recommended.