ESX 4 to 4.1 upgrade

I had a requirement this week to move our infrastructure to ESX 4.1 prior to upgrading to ESXi5.1. So I used this knowledge base to get me there it was pretty straight forward. We weren’t able to do this using update manager as vCenter was at version 5, which is only supporting ESXi updates.

Step 1 Download the preupgrade patch and the upgrade patch from vmware website. This will move our environment to 4.1 update 3.

Step 2 Use Winscp to copy files to /tmp/41Upgrade on the remote host.

Step 3 Put host to be upgraded into maintenance mode.

Step 4 Use putty to connect to the host to run the updates. I had to update the path statement on the way so that the installer would complete without errors.

Su to Switch to root user
Enter password
Export PATH=$PATH:/usr/sbin
Esxupdate update –bundle /tmp/41Upgrade/{append the preupgrade file name here}

Once the preupgrade has finished run the upgrade. If the update completes without errors reboot.

VMware KB Article to upgrade to 4.1