This is correct: "DC/OS is better for running stateful services and then you can use K8 to run your stateless services"
Data services run directly on DC/OS via application-aware schedulers. They have the operational logic for how to bring up say a Cassandra cluster correctly, how to upgrade it to a new version without breaking it, change config, scale up, etc. All things you usually have to figure out yourself. When you run k8s on DC/OS you get these same benefits.
This is correct: "DC/OS is better for running stateful services and then you can use K8 to run your stateless services"
Data services run directly on DC/OS via application-aware schedulers. They have the operational logic for how to bring up say a Cassandra cluster correctly, how to upgrade it to a new version without breaking it, change config, scale up, etc. All things you usually have to figure out yourself. When you run k8s on DC/OS you get these same benefits.