Obligatory: DON’T DO THIS IN A PRODUCTION ENVIRONMENT, YOU SHOULDN’T REALLY DO THIS AT ALL
I use two Atom C2550 servers in my homelab so I can have a little redundancy and can offload some low priority, low CPU intensive servers off my main server, but the new ESXi 8.0 doesn’t support them any longer. Here are the steps I used to rectify the situation. It works with both VCenter Images and command line updates.
Step 1: Edit /bootbank/boot.cfg & /altbootbank/boot.cfg and and add “allowLegacyCPU=true” (no quotes, a space between options) on the “kernelopt” line, then reboot. Example:
Step 2: (Skip below for command line) You can now use the Image Update built into VSphere to update the unsupported CPU.
Alternative Step 2: I use this website to get the command line to update to a specific version: esxi-patches.v-front.de add “–no-hardware-warning” (no quotes) to the update command. Run the command (it took a few minutes of not doing anything) then reboot.
My example command:
esxcli network firewall ruleset set -e true -r httpClient
esxcli software profile update -p ESXi-8.0a-20842819-standard -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml --no-hardware-warning
esxcli network firewall ruleset set -e false -r httpClientResult:
