6.5.1

Table Of Contents
Figure 31. UEFI Secure Boot
UEFI firmware
Management apps (hostd, dcui, etc.)
Drivers and modules
ESXi base system
VMkernel
bootloader
Secure boot VIB verifier
VMware
public key
UEFI secure boot
enabled machine
UEFI CA
public key
Root
of trust
1
1
2
VMware
public key
With secure boot enabled, the boot sequence proceeds as follows.
1 Starting with vSphere 6.5, the ESXi bootloader contains a VMware public key. The bootloader uses
this key to verify the signature of the kernel and a small subset of the system that includes a secure
boot VIB verifier.
2 The VIB verifier verifies every VIB package that is installed on the system.
At this point, the entire system boots with the root of trust in certificates that are part of the UEFI firmware.
UEFI Secure Boot Troubleshooting
If secure boot does not succeed at any level of the boot sequence, an error results.
The error message depends on the hardware vendor and on the level at which verification did not
succeed.
n
If you attempt to boot with a boot loader that is unsigned or has been tampered with, an error during
the boot sequence results. The exact message depends on the hardware vendor. It might look like
the following error, but might look different.
UEFI0073: Unable to boot PXE Device...because of the Secure Boot policy
n
If the kernel has been tampered with, an error like the following results.
Fatal error: 39 (Secure Boot Failed)
vSphere Security
VMware, Inc. 106