When attempting to upgrade ESXi hosts in a cluster to version 8.0 Update 3h (Build 25067014), the corresponding version does not appear in the update view despite a baseline being created in vSphere Lifecycle Manager (vLCM). This prevents the initiation of the remediation process via the traditional baseline method.
VMware vSphere 8.0
With the release of vSphere 8.0, VMware has deprecated vSphere Lifecycle Manager Baselines (formerly known as vSphere Update Manager or VUM). While baselines still exist for legacy support, the preferred and primary method for managing host lifecycles in vSphere 8.x is "vSphere Lifecycle Manager Images."
To resolve this, the cluster management must be transitioned from Baselines to Images.
Step 1: Obtain the Upgrade Image
Step 2: Transition Cluster to Image-Based Management
Click SAVE.
Perform a Check Compliance and run the Hardware Compatibility (HCL) check before proceeding with remediation.