Another mapSet attribute affecting shard placement is the
developmentMode attribute. By default, this value is set to
true, meaning the deployment is in development mode. Development mode allows primary and replica shards to be placed on the same host. It also allows us to start all of our containers on the same host, be it our laptop, desktop, test system, or wherever. We cannot run these examples without the development mode as well as without at least two different host operating systems, whether they may be physical boxes or virtual.
When a deployment is not in development mode, two shards from the same partition cannot live on the same host, even if they are in different containers. With
developmentMode="false", multiple ...