Setup guide
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VMware vSphere® 5.0 Upgrade
Best Practices
In addition to running supported hardware, each ESXi host must meet the requirements for number and type of
CPUs, amount of memory, and supported network and storage devices. For information on server sizing and
capacity planning, refer to the vSphere Installation and Setup and vSphere Resource Management guides.
Verifying ESX/ESXi Host Version
Only hosts running ESX/ESXi 4.x can be directly upgraded to ESXi 5.0. Hosts running older releases must first
be upgraded to ESX/ESXi 4.x. While planning your ESXi 5.0 upgrade, evaluate the benefit of upgrading older
servers against the benefit of replacing them with new hardware.
Boot-Disk Free-Space Requirements
The upgrade procedure utilizes free space on the host’s boot disk. The amount of free space depends on
whether you are upgrading from ESX or ESXi and whether you are using the ESXi Installer or Update Manager.
Upgrading from ESXi 4.x
When upgrading from ESXi 4.x, using either the ESXi Installer or Update Manager, a minimum of 50MB of free
space is required in the host’s local VMware vSphere® VMFS (VMFS) datastore. This space is used to temporarily
store the host configuration.
Upgrading from ESX 4.x
When upgrading from ESX 4.x, the free-space requirements vary depending on whether you are using the ESXi
Installer or Update Manager.
ESXi Installer
When using the ESXi Installer, a minimum of 50MB of free space is required in the host’s local VMFS datastore.
This space is used to temporarily store the host configuration.
VMware vSphere Update Manager
When using Update Manager, in addition to having 50MB of free space on the local VMFS datastore, there is an
additional requirement of 350MB free space in the “/boot” partition. This space is used as a temporary staging
area where Update Manager will copy the ESXi 5.0 image and required upgrade scripts.
NOTE: Due to dierences in the boot disk partition layout between ESX 3.5 and ESX 4.x, ESX 4.x hosts
upgraded from ESX 3.x might not have the required 350MB of free space and therefore cannot be upgraded to
ESXi 5.0 using Update Manager. In this case, use the ESXi Installer to perform the upgrade.
ARCHITECTURE UPGRADE TOOL BOOT DISK VMFS /BOOT
ESXi ESXi Installer or
Update Manager
50MB n/a
ESX ESXi Installer 50MB n/a
ESX Update Manager 50MB 350MB
Table 1 . Summary of Boot-Disk Free-Space Requirements
Disk Partitioning Requirements
In addition to requirements regarding available free space, the upgrade also has requirements pertaining to the
boot disk partition table. Upgrading an existing ESX/ESXi 4.x host to ESXi 5.0 modifies the host’s boot disk. As
such, a successful upgrade is highly dependent on having a supported boot disk partition layout. Whether the
upgrade will simply update files on the boot disk or actually modify the partition table depends on whether you
are upgrading from ESX or ESXi.