Upgrading from VMware ESX 3.5.0 v123630 to ESX 4.1.0 v348481

NOTE: you have to go via ESX 4.0.0 398348 – you cannot go directly to 4.1


NOTE: with new software comes new hardware requirements. Are your servers on the vSphere supported list?

First, upgrade vCenter Server to v345043 (perhaps take a snapshot or VDR of it first)

(afterwards, this upgrade might not allow your current vm hosts to connect to the vsphere vcenter, but you can still connect to them directly. This is not a problem as we’re about to upgrade the hosts anyway)

SSH to the ESX host you want to upgrade, to check the amount of disk space.

Use df -h

By default, ESX does not let you SSH to the shell as ROOT, so create another user (admin), give it a password and permissions equivalent to root.

You get the option to create another user on install, or if you didn’t do this, use the vSphere client to connect directly to the ESX host and use Users & Groups to create your admin user.

Once logged into the shell (using your admin account), type

su – root

to connect as ROOT.

We used the following versions / files to upgrade:

“ESX-4.0.0-update03-398348.iso” with Host Update Utility 4, Build 385281

(this is to upgrade from ESX 3.5.0 v123630 to ESX 4.0.0 v398348)

Then copy the “upgrade-from-esx4.0-to-4.1-update01-348481.zip” to the local datastore of the ESX or ESXi host you want to upgrade and run the zip file.

(log in to the shell as admin, via SSH)

It does hang for a while at certain percentages, but you can always check what the server is upto via your RAC. Which hopefully is configured. I've found that Firefox seems to be the best browser for handling the Java screen, it seems to work much more consistently than IE, or Chrome.