They backed up the data and forgot how the server was built

They backed up the data and forgot how the server was built

Hosting reseller, server died. Data backups: perfect. But nginx configs, cron jobs, firewall rules, SSL setup, the exact PHP extensions — none of it was captured. They had the files and no idea how to make them run. Rebuilding the environment from memory took 4 days while 60 client sites sat dark.

Now they snapshot full server images, not just /var/www.

Data without its environment is a pile of bytes. Back up the machine, not just the folder. Change my mind.