Quick Tip - Changes to building custom ESXi images in vSphere 8

Historically, when a new version of ESXi is released, customers will use vSphere Image Builder either through the vSphere Image Builder UI or PowerCLI Image Builder cmdlets to create a custom ESXi image to include additional drivers such as the USB Network Native Driver for ESXi Fling.

Note: The current version of the USB Network Native Driver for ESXi Fling is not compatible with ESXi 8.0 and a new version of the driver will be needed. There is currently no ETA on when a new version will be available.

Typically, customers will use their existing vCenter Server deployment, which is usually running an older version to create their new custom ESXi image. This means you are importing a newer ESXi release into your vCenter Server or in the case of the PowerCLI Image Builder cmdlets, you are using an older release of PowerCLI. While this may have worked with previous releases, the assumption that vSphere Image Builder is "forward" compatible with future releases of ESXi is actually an incorrect assumption that many have made, including myself.

I bring this up because in vSphere 8, there have been changes in ESXi where this incompatibility will be observed when attempting to create a custom ESXi 8.0 image using a non-compatible vCenter Server or a PowerCLI release.

This is also the reason you do not see an ESXi 8.0 Image in the vSphere Lifecycle Manager (vLCM) depot by default for those running vSphere 7.x as it understands this incompatibility and will also prevent you from importing an ESXi 8.0 Image Profile.

However, if you use Image Builder (UI or PowerCLI) in a vSphere 7.x environment, which will allow you to import ESXi 8.0 Image Profile, but it does not understand this incompatibility and you will still run into issues with following errors:

is claimed by multiple non-overlay VIBs

To properly create a custom ESXi 8.0 image, you will need to either use a vCenter Server that is already running vSphere 8.0 or wait for an upcoming PowerCLI (12.8) release that will be compatible with vSphere 8 for those that do not have an existing vCenter Server.

Lastly, since there have been some questions about the size of the ESXi 8.0 Image Profile / ISO, here is a quick tidbit on the reason for that:

The ESXi 8.0 ISO / Offline Bundle is larger because it contains BOTH the x86 and Arm bits (latter for running vSphere Distributed Service Engine). You can identify the Arm VIBs by looking for "esxio" in the filenames

— William Lam (@lamw.bsky.social | @*protected email*) (@lamw) October 28, 2022

Note: It is currently NOT supported to create a custom ESXi 8.0 image that only contains the x86 VIBs, this will impact future upgrades as there are built-in pre-checks to ensure all VIBs (x86 and Arm) are contained within your installation.