When trying to upgrade an ESXi host using the console, I received the error below. In this case I was attempting to upgrade to version 7 Update 3k.
[HardwareError] Hardware precheck of profile ESXi-7.0U3k-21313628-standard failed with warnings: <CPU_SUPPORT WARNING: The CPU in this host is not supported by ESXi 7.0.3. Please refer to the VMware Compatibility Guide (VCG) for the list of supported CPUs.>
The error will prevent the upgrade from continuing. However, you can force the upgrade of a system with a legacy processor using these steps:
- In the root file system of ESXi, edit /bootbank/boot.cfg using vi
- On the line that starts with kernelopt=, add the following to the end: allowLegacyCPU=true
- Save the file and reboot the host
- Then attempt the upgrade again (e.g., using esxcli software profile update)