TL;DR — A security breach took down a site running on a 10-year-old Debian server with an obsolete LAMP stack. No access to the original infrastructure, no time to understand it. This is what I did, in what order, and why. The system is still in production. The migration is still ongoing. The site went down because of a security breach. Not a gradual degradation, not a performance problem we'd been ignoring. A breach. The system was offline, and getting back in meant dealing with infrastructure that hadn't been touched in over a decade — a Debian server, no longer receiving updates, running a LAMP stack that had been obsolete for years. No access to the original setup. No time to understand it properly. The only priority was getting it back up. That's where this started. What I was looking at A system doesn't have to be old to become unmaintainable. Five to seven years of incremental pressure is enough. The system was 5 to 7 years old, but the infrastructure underneath it was older.…