Comment by 4ndrewl

https://downdetectorsdowndetectorsdowndetector.com/

Downdetection can be thought of as a directed graph, or digraph*.

From there, the "who's watching who?" can become mathematically interesting.

* https://en.wikipedia.org/wiki/Directed_Graph

Given enough of them, some fraction will always be down. It would be helpful if we had a site that could track that ratio.

It's a centralization vs decentralisation vs distributed system question.

Since down detectors serve to detect failures of centralized (and decentralized systems) the idea would be to at least get that right: a distributed system to detect outages.

You basically run detectors that heartbeat each others. Just a few suffice.

Once you start to see clusters of detectors go silent, you can assume things are falling apart, which is fine so long as a few remain.

Self healing also helps to make the web of nodes resilient to inevitable infrastructure failures.

It's down detectors all the way down

here's a page that monitors that page: https://onlineornot.com/website-down-checker?requestId=jCfaD...

Looks like it's hosted in London?

We could create a linked list of these and just refer to the N’th one as N-down detector.