So with the release of ESXi 5.5 I decided to follow my previous instructions and upgrade my hosts using the esxcli commands.
1. Place the Host into Maintenance Mode and ensure that there are no running VM’s on the host.
2. Ensure you have SSH enabled
3. Make sure that the Outbound HTTP rule is enabled, either by using the console or via the command line later on (command line is esxcli network firewall ruleset set -e true -r httpClient )
4. SSH into the host using your favourite client (in my case, PuTTY)
5. Check Connectivity to the VMware’s Online Depot using the following :-
esxcli software sources profile list -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml
As long as you get a return from this it means you’re firewall connectivity is correctly in place. The two highlighted files are for the latest standard image and the no VMware Tools image, take a note of the version you want to install.
6. Run the following to download and install the required update.
esxcli software profile update -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml -p ESXi-5.5.0-1331820-standard
The upgrade will take a couple of minutes (depending on your internet connection) and will require a reboot to finish the upgrade.
7. Confirm that you’re running the latest version on the host.
8. Upgrade all remaining hosts.
All in all this took no more than 10 minutes for both hosts.
Thanks to William Lam for his post A Pretty Cool Method of Upgrading to ESXi 5.1 which gave me the idea for 5.1u1 and subsequently 5.5.