Platform & DevOps·Running it: capacity, failure and recovery
the managed database will be restarted by the provider at some point inside a four-hour window you chose months ago.
Maintenance window
Also calledpatch window, scheduled maintenance
A declared period in which disruptive operations — provider patching, node replacement, version upgrades — may occur. Managed services apply them whether or not you have planned for them, so the window is a commitment you have made even if nobody remembers making it. Treating provider maintenance as a routine failover you must survive, rather than as an event you must be awake for, is the difference between a mature platform and a fragile one.