It was 2:00 AM on a Tuesday, and the production SQL server had screamed its last breath at 10:00 PM. The company’s entire inventory system was frozen. And the only way to fix it was to log into the old ESXi 5.0 host sitting in a corner of the data center like a forgotten zombie.

Third run: The installer finished. A green checkmark. Leo almost wept.

He double-clicked the icon—that chunky, grey, 2010-era cube. The login screen appeared. He typed the IP of the zombie host. Username: root. Password: password123.