Understanding the Requirements:

The cluster is in a dark site, meaning it does not have access to the internet. This requires offline methods to update firmware.

Download the Update Firmware:

Option A: Download the update firmware .tgz file from the Nutanix Portal:

The administrator needs to download the firmware update package from the Nutanix Support Portal. This package typically includes the necessary firmware files bundled in a .tgz file format.

This step ensures that the correct and latest firmware version is obtained directly from Nutanix, which is essential for maintaining compatibility and stability​​.

Stage the Dark Site Bundle:

Option B: Download the dark site bundle and stage it on an internal webserver:

Since the cluster does not have internet access, the administrator must use the dark site bundle. This involves downloading the necessary files and staging them on an internal web server accessible by the Nutanix cluster.

This internal web server acts as a local repository for the firmware updates, ensuring that the cluster can access and apply the updates without needing an internet connection​​.

Conclusion:

To update the firmware in a dark site environment, the correct steps are to download the firmware .tgz file from the Nutanix Portal and stage the dark site bundle on an internal web server.

References: Nutanix documentation on dark site management and firmware updates.