My website runs on a dedicated Debian LAMP server . I would like to update the system (let's say I have a pretty old Debian version and I want to reinstall everything from scratch)
What strategy can I use to not have my website down while I am reinstalling everything?
Addendum
Of course I know I can buy another server in the meanwhile and change the DNS whenever it's done. But this doubles my work.
Aren't some service that maybe can act as a proxy-cacher for a limited amount of time? Maybe what does CloudFlare but caching everything not just images.