You might need to roll back to ESX 3.5 if the upgrade to ESX 4.1 does not work as expected in your environment. Optionally, you can remove the ESX 4.1 boot option from the ESX bootloader menu and perform a complete roll back to ESX 3.5.


Roll backs are supported only for upgrades from ESX 3.5 to ESX 4.1 using vCenter Update Manager.

Consider the following points:

Any changes made to the ESX 4.1 service console are lost after the rollback.

Any changes made to virtual machines will persist after the rollback.

If you upgraded the virtual machine hardware, the virtual machines will not work after you perform the ESX rollback. To avoid this situation, take a snapshot of the virtual machine before you upgrade the virtual machine hardware. After you run the ESX rollback script, boot into ESX 3.5 and revert to the snapshot.

Only a system administrator can perform this optional procedure.


Run the rollback-to-esx3 command in the ESX 4.1 service console.

The rollback-to-esx3 command reconfigures the bootloader to boot into ESX 3.5 and removes the ability to boot into ESX 4.1.

You can include the optional -f (force) flag. If you omit the -f flag, you are prompted to confirm that you want to roll back to ESX 3.5.


Reboot the server.

While the host is powering on, observe that the boot menu has changed to ESX 3.5.


After the host boots into ESX 3.5, delete the ESX 4.1 service console VMDK folder from the VMFS datastore.

The service console VMDK folder name has the following format: esxconsole-<UUID>.