How to Migrate ESXi 4 to ESXi 5.0

VMware has recently released its new VM hypervisor product, VMware ESXi 5.0. VMware is replacing its current ESX model with ESXi and the biggest change (between ESX and ESXi) is the architecture

Pre-Requisites:

Check the server hardware you are installing ESXi 5 onto is supported and on the VMware HCL.
Login to the VMware license portal to check/upgrade/buy your vSphere licenses.
Read the ESXi Setup Guide to ensure you understand the pre-requisites.
Download the VMware ESXi 5 ISO file from the VMware download area.
Burn the ESXi 5 ISO to a CD.
Disconnect all Fibre Channel connections (if any) and boot the server from the CD.

First make sure you upgrade the vCenter server, you cannot connect an ESXi server to a vCenter 4.1 U1 server (or earlier).Put the host(s) you want to upgrade into maintenance mode, vMotion VMs to other hosts or shutdown VMs are required).Reboot the server and boot from the VMware ESXi 5.0 installation CD media.

Select “ESXi-5.0.0-xxxxx-standard Installer”

Press “Enter”

Read and accept the license agreement. Press “F11”

Select the disk to upgrade to ESXi. Ensure this is not a shared VMFS datastore on a SAN (you should have unplugged the FC connections). Press “Enter”.

Here are the upgrade/migrate options:

Force Migrate ESX, preserve VMFS datastore

Install ESXi, preserve VMFS datastore

Install ESXi, overwrite VMFS datastore

If you are migrating note only some of the settings are migrated over. A full list of the files/settings migrated can be found in the upgrade guide.

Force Migrate ESXi, Preserve VMFS Datastore: This will take your current installation and configuraiton and attempt an upgrade/migration and keep your VMFS Datastores intact, so your VMs will be preserved if things go wrong.

Install ESXi, Preserve VMFS Datastore: This will install a fresh copy of ESXi 5.0 and leave your VMFS datastores intact, this will erase all custom configurations, it’s a clean slate basically and you will have to re-add your VMs back to your inventory once you have reconfigured your host server.

Install ESXi, Overwrite VMFS Datastore: This does exactly what it sounds, it will install a clean copy of ESXi 5.0 and overwrite your current datastores – you will LOOSE all information on that datastore.

Note you will get a warning about any 3rd party software installed that cannot be migrated. In this case it is a network and scsi driver, verify this will not pose an issue once migrated.

Press “Enter”

Press “F11” to force the migration and preserve the VMFS datastore.