6.5.1

Table Of Contents
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If a package (VIB or driver) has been tampered with, a purple screen with the following message
appears.
UEFI Secure Boot failed:
Failed to verify signatures of the following vibs (XX)
To resolve issues with secure boot, follow these steps.
1 Reboot the host with secure boot disabled.
2 Run the secure boot verification script (see Run the Secure Boot Validation Script on an Upgraded
ESXi Host).
3 Examine the information in the /var/log/esxupdate.log file.
Run the Secure Boot Validation Script on an Upgraded ESXi Host
After you upgrade an ESXi host from an older version of ESXi that did not support UEFI secure boot, you
may be able to enable secure boot. Whether you can enable secure boot depends on how you performed
the upgrade and whether the upgrade replaced all of the existing VIBs or left some VIBs unchanged. You
can run a validation script after you perform the upgrade to determine whether the upgraded installation
supports secure boot.
For secure boot to succeed, the signature of every installed VIB must be available on the system. Older
versions of ESXi do not save the signatures when installing VIBs.
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If you upgrade using ESXCLI commands, the old version of ESXi performs the installation of the new
VIBs, so their signatures are not saved and secure boot is not possible.
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If you upgrade using the ISO, new VIBs do have their signatures saved. This is true also for vSphere
Uprade Manager upgrades that use the ISO.
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If old VIBs remain on the system, the signatures of those VIBs are not available and secure boot is
not possible.
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If the system uses a 3rd-party driver, and the VMware upgrade does not include a new version of
the driver VIB, then the old VIB remains on the system after upgrade.
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In rare cases VMware might drop ongoing development of a specific VIB without providing a new
VIB that replaces or obsoletes it, so the old VIB remains on the system after upgrade.
Note
UEFI secure boot also requires an up-to-date bootloader. This script does not check for an up-to-date
bootloader.
Prerequisites
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Verify that the hardware supports UEFI secure boot.
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Verify that all VIBs are signed with an acceptance level of at least PartnerSupported. If you include
VIBs at the CommunitySupported level, you cannot use secure boot.
vSphere Security
VMware, Inc. 107