You can boot the ESXi installer from a CD, DVD, or USB flash drive to upgrade ESX/ESXi 4.x, ESXi 5.0.x, and 5.1.x hosts to ESXi 5.5.

Before you begin

About this task

Important:

If you are performing a fresh ESXi installation, see the vSphere Installation and Setup documentation. The instructions in this vSphere Upgrade documentation are for an upgrade or migration of ESXi or ESX.

Before upgrading, consider disconnecting your network storage. This action decreases the time it takes the installer to search for available disk drives. When you disconnect network storage, any files on the disconnected disks are unavailable at installation. Do not disconnect a LUN that contains an existing ESX or ESXi installation. Do not disconnect a VMFS datastore that contains the Service Console of an existing ESX installation. These actions can affect the outcome of the installation.

Important:

After you upgrade or migrate your host to ESXi 5.x, you cannot roll back to your version 4.x ESX or ESXi software. Back up your host before you perform an upgrade or migration, so that, if the upgrade or migration fails, you can restore your 4.x host.

Procedure

  1. Insert the ESXi installer CD/DVD into the CD/DVD-ROM drive, or attach the Installer USB flash drive and restart the machine.
  2. Set the BIOS to boot from the CD-ROM device or the USB flash drive.

    See your hardware vendor documentation for information on changing boot order.

  3. In the Select a Disk panel, select the drive on which to install or upgrade ESXi and press Enter.

    Press F1 for information about the selected disk.

    Note:

    Do not rely on the disk order in the list to select a disk. The disk order is determined by the BIOS. On systems where drives are continuously being added and removed, they might be out of order.

  4. If the installer finds an existing ESX or ESXi installation and VMFS datastore you can choose from the following options:
    • Upgrade ESXi, preserve VMFS datastore

    • Install ESXi, preserve VMFS datastore

    • Install ESXi, overwrite VMFS datastore

    If an existing VMFS datastore cannot be preserved, you can choose only to install ESXi and overwrite the existing VMFS datastore, or to cancel the installation. If you choose to overwrite the existing VMFS datastore, back up the datastore first.

    If you are migrating a 4.x host that contains custom VIBs that are not included in the ESXi installer ISO, the option Upgrade ESXi, preserve VMFS datastore is replaced with Force Migrate ESXi, preserve VMFS datastore.

    Caution:

    Using the Force Migrate option might cause the upgraded host to not boot properly, to exhibit system instability, or to lose functionality. If you are upgrading a 5.0.x or 5.1.x host, supported custom VIBs that are not included in the ESXi installer ISO are migrated. You do not need to to select the Force Migrate option. See Upgrading Hosts That Have Third-Party Custom VIBs.

  5. Press F11 to confirm and start the upgrade.
  6. When the upgrade is complete, remove the installation CD/DVD or USB flash drive.
  7. Press Enter to reboot the host.
  8. Set the first boot device to be the drive on which you upgraded ESXi in 3.

    If an existing VMFS datastore cannot be preserved, you can choose only to install ESXi and overwrite the existing VMFS datastore, or to cancel the installation. If you choose to overwrite the existing VMFS datastore, back up the datastore first.

    See your hardware vendor documentation for information on changing boot order.