NSX Preparation Fails with 'Discovered Node is Already Prepared' Error on Reinstalled ESXi Host

Products

• VMware NSX

Issue/Introduction

• While preparing NSX on ESXi has following error: 

Error: General error has occurred. Discovered node with id:<Discovered Node ID:host-###> is already prepared having fabric node id:<Transport Node UUID>

 

• ESXi underwent an OS reinstallation, and it had been removed from vCenter without also being removed from NSX. 

Environment

VMware NSX

Cause

When an ESXi host is removed directly from vCenter without first removing NSX, it can result in entries for that host to remain in the NSX database.

The correct procedure to remove NSX from a single host:

• Uninstall NSX data Center from a managed host in a vSphere Cluster 

Resolution

Remove NSX from ESXI: 

1) Place the ESXi host into maintenance mode.

2) Move the ESXi outside the Cluster (this will uninstall NSX from this host).

3) Confirm the NSX VIBs are removed from this host by SSH and running the following command: esxcli software vib list | grep -i "nsx"

4) Once the NSX VIBs are removed, move the Host back to the Cluster which should trigger the NSX install again.

 

If you are not able to perform the above steps, proceed with workaround mentioned in the KB#:319975 

Additional Information

Troubleshooting NSX Uninstall Process