DC/OS

DC/OS is another distributed kernel OS built using Apache Mesos for cluster management. Apache Mesos is a cluster manager that integrates seamlessly with container technologies such as Docker for scheduling and fault tolerance. Apache Mesos is in fact a generic cluster management tool that is also used in big data environments such as Hadoop and Cassandra. It also gels well with several batch scheduling, PaaS platforms, long-running applications, and mass data storage systems. It provides a web dashboard for cluster management.

Apache Mesos's complex architecture, configuration, and management makes it difficult to adapt directly. DC/OS makes it easy and significantly straightforward. DC/OS runs on top of Mesos and does the job of what kernel does on your laptop OS, but over a cluster of machines. It provides services such as scheduling, DNS, service discovery, package management, and fault tolerance over a collection of CPUs, RAM, and network resources. DC/OS is supported by a wealth of developer community, rich diagnostics support, and management tools using GUI, CLI, and API.

ACS, which was discussed previously, has a reference implementation for DC/OS. Within a few clicks Azure makes it easy to build a DC/OS cluster on the cloud and makes it ready to deploy applications. The same sets of services are provided for on premise data centers or private clouds using Azure Stack (Azure Stack is an OS provided by Microsoft for managing private clouds). You also get an additional benefit of integrating with other rich sets of services provided by Azure for increasing the agility and scalability.

Two other cluster managers that are not discussed here are Amazon EC2 Container Service, which is built on top of Amazon EC2 instances and uses shared state scheduling services, and CoreOS Tectonic, which is Kubernetes as a service on AWS (Amazon's cloud offering).