For some reason I have friends / colleagues telling me that when scaling (up and down for this example) that no downtime occurs. Well, not only does Microsoft documentation say differently, I will show it. So let’s test it out. Before the practical test, this is the official stance. “There is a switch over period where connectivity is lost to the database for a short amount of time, which can be mitigated using retry logic”.
Retry logic is an important part of any application. We tend to forget about it with on-prem applications talking to on-prem databases, but that’s a mistake.