Here we are showing, how to cleanly uninstall the Nimble Connection Manager before an ESXi Upgrade.
NCM is a software plug in from Nimble which maintains the optimal number of iSCSI sessions from host to the Nimble storage array group which is balanced across the hosts NIC’s. PSP for VMware Pluggable Storage Architecture automatically directs the I/O request for the Nimble to the most favorable route If you’re using HPE Nimble storage arrays to back your VMware environment.

 

Case-1: Can’t start new version.

After upgrade if ESXi server stuck at ‘’Loading module nimble_psp_directed’’ and fails to boot. Else skip case-1 and go directly to Nimble Connection Manager uninstall steps.

Updated version fails to boot due to non-compatible NCM version. Need to uninstall the NCM first then do the ESXi upgrade and install the latest NCM version. For this we have to revert back to the previous ESXi version first then do the NCM removal.

1. Force reboot the ESXi server.
2. When the hypervisor starts booting, enter Recovery Mode.
## hit SHIFT+R to go to Recovery Mode.
3. Now hit Y to restore the previously installed ESXi version.

 

Nimble Connection Manager Un-installation Process:

1.  Place the affected host in Maintenance Mode.

Nimble Connection Manager Un-installation Process
For older version.
Right-click the host and select Maintenance Mode > Enter Maintenance Mode.

2.   Connect to the host via ESXi CLI.

3.   Run the below commands.
           /etc/init.d/sfcbd-watchdog stop
            esxcli software vib remove -n nimble-ncs –maintenance-mode
            esxcli software vib remove -n nimble-psp –maintenance-mode

4.  Reboot the ESXi host.


5.  Install the latest NCM version, for ESXi 6.5/6.7 latest NCM version is 5.1.
For NCM installation you can refer our blog at URL
https://www.hex64.net/upgrade-nimble-connection-manager-on-esxi-6-5/

Verify NCM Installation:

From the root directory, run the command:
esxcli software vib list|grep nimble

If nimble-ncs and nimble-psp does not appear in the list, the uninstallation was successful.
If nimble-ncs and nimble-psp appear in the list, the installation was successful (as in screenshot).