To upgrade ESXi 5.5 hosts or ESXi 6.0 hosts to ESXi 6.5, you can boot the ESXi installer from a CD, DVD, or USB flash drive.
Before upgrading, consider disconnecting the 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 ESXi installation.
- Verify that the ESXi installer ISO in one of the following locations.
Note: You can also use PXE to boot the ESXi installer to run an interactive installation or a scripted installation. See PXE Booting the ESXi Installer.
- On CD or DVD. If you do not have the installation CD or DVD, you can create one. See Download and Burn the ESXi Installer ISO Image to a CD or DVD
- On a USB flash drive. See Format a USB Flash Drive to Boot the ESXi Installation or Upgrade
- Verify that the server hardware clock is set to UTC. This setting is in the system BIOS.
- ESXi Embedded must not be on the host. ESXi Installable and ESXi Embedded cannot exist on the same host.
- If you are upgrading an ESXi host, supported custom VIBs that are not included in the ESXi installer ISO are migrated. See Upgrading Hosts That Have Third-Party Custom VIBs
- See your hardware vendor documentation for information about changing the boot order.
- Insert the ESXi installer CD or DVD in the CD-ROM or DVD-ROM drive, or attach the Installer USB flash drive and restart the machine.
- Set the BIOS to boot from the CD-ROM device or the USB flash drive.
- 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.
- Upgrade or install ESXi if the installer finds an existing ESXi installation and 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.
- Press F11 to confirm and start the upgrade.
- Remove the installation CD or DVD or USB flash drive when the upgrade is complete.
- Press Enter to reboot the host.
- Set the first boot device to be the drive which you selected previously when you upgraded ESXi.