Our web application uses various web services, most of which are not managed by us, but by an external service provider (e.g. Auth0 is one of those services).
Recently, our application failed because a critical service was not reachable. Various "connection attempt failed" messages showed up in our error logs along with the problematic IP address, so we were able to tell which service it was. During analysis, we discovered that the service was reachable both from our office as well as from various other places we tested. So the service itself was not the problem. This was also confirmed by the service provider.
I suspect a networking issue to be the root cause, but I'm not sure.
What is the recommended approach to handle such situations? How can we avoid it in the future?
By the way, our application runs on Microsoft Azure as Azure Web Site, but this is probably not important for this question.
