Upgrading ESX 4.0 to 4.1 from the command line

I’m back from my camper trip through France and decided to finally upgrade my ESX 4.0 hosts to version 4.1. One of my ESX servers is hosting the virtual machine with vCenter (local storage) and you cannot use the vSphere Host Update utility to upgrade ESX 4.x hosts. This utility is only for standalone ESX 3.x and ESXi hosts. A standalone host is an ESX  host that is not managed by vCenter Server. So I had to find another way to upgrade this ESX host. The resolution for this problem is the esxupdate Command-Line Utility available in the service console.

The first step is to download the following zip files from VMware’s website and copy the files to the service console:

pre-upgrade-from-ESX4.0-to-4.1.0-0.0.260247-release
upgrade-from-ESX4.0-to-4.1.0-0.0.260247-release.zip

The second step is to install the pre-upgrade using esxupdate, this can be done without a reboot and without maintenance mode.

esxupdate --bundle=pre-upgrade-from-ESX4.0-to-4.1.0-0.0.260247-release.zip update

Now you have to put you ESX host into maintenance mode, this can also be done with the command line otherwise you will get this message: Description - Maintenance mode is not enabled or could not be determined.

vimsh -n -e /hostsvc/maintenance_mode_enter

We can finally upgrade the ESX host to 4.1 with the following command line:

esxupdate --bundle=upgrade-from-ESX4.0-to-4.1.0-0.0.260247-release.zip update

The update is completed successfully, but the system needs to be rebooted for the
changes to be effective.

Reboot... vimsh -n -e /hostsvc/maintenance_mode_exit Done

After finishing this article I discovered a similar one written by Tomi Hakala over at vReality, great work Tomi.