Design a system to upgrade hundreds of thousands of machines on the Moon.

Focus on the unique challenges of operating in a lunar environment, such as limited resources, communication delays, and harsh conditions. Consider the architecture of the upgrade system, including how you would manage remote updates, ensure reliability, and handle potential failures. Discuss the scalability of your solution, including how to efficiently deploy upgrades across a vast number of machines. Be prepared to address safety protocols and the need for redundancy in your design, as well as how you would gather user feedback or performance data post-upgrade.