If you are talking about dedicated servers: Those are unmanaged, Hetzner does not monitor those. Regarding grandparent: What kind of hardware failure? I had to

If you are talking about dedicated servers: Those are unmanaged, Hetzner does not monitor those. Regarding grandparent: What kind of hardware failure? I had to change different types of hardware in the past. For HDD changes you send a full SMART result + possibly the logs showing that the RAID kicked the faulty disk and they replace the faulty disk in 30 minutes (and one time even apologized that it took 2 hours for a low-priority-support server). In all cases the actual downtime was < 5 minutes, because of RAID. For possibly broken fans I simply stated that according to my Munin logs show consistent temperatures near the upper limit and asked whether they could take a look. They added an additional fan within 30 minutes, again with actual downtime < 5 minutes. Most of my replacements were during the night in Germany, that might have helped, because there are possibly less requests in parallel. And I always had hard logs proving my HDD failures.