@Jean-baptiste Foundation is failing with error - “Failed to validate AOS package lcm_nos_5.20.1.1.tar.gz” because it looks like wrong AOS bundle was uploaded in foundation.

Based on the above error, AOS LCM Bundle - LTS (Version: 5.20.1.1) with filename: lcm_nos_5.20.1.1.tar.gz is being used instead of using the nutanix_installer_package-version#.tar.gz file for AOS install via foundation. 

Hence in order to resolve this issue, kindly go to AOS Downloads Page on the Nutanix Support portal and download the nutanix_installer_package-version#.tar.gz file for AOS 5.20.1.1 (filename - nutanix_installer_package-release-euphrates-5.20.1.1-stable-726ea8f7dc4bca156d3e3f63cd7982eecb70c8cb-x86_64.tar.gz) which will be used for imaging the nodes with desired AOS release via foundation. Kindly refer to the Foundation Field Installation Guide for more details on this one.