Why Docker is a winner versus VMs

This is a quote from the blog A Not Very Short Introduction to Docker by Anders Janmyr, perhaps one of top techie bloggers in the world who speaks with such clarity, that even non-techies understand.

Now when everything is crystal clear, what does this mean? It means that Docker containers are smaller, faster, and more easily integrated with each other than VMs as the table illustrates.

The size of a small virtual machine image with Core OS is about 1.2 GB. The size of a small container with busybox is 2.5 MB.

The startup time of a fast virtual machine is measured in minutes. The startup time of a container is often less than a second.

Integrating virtual machines running on the same host must be done by setting up the networking properly. Integrating containers is supported by Docker out of the box.

So, containers are lightweight, fast and easily integrated, but that is not all.

Docker is a Contract

Docker is also the contract between Developers and Operations. Developers and Operations often have very different attitudes when it comes to choosing tools and environments.

Developers want to use the next shiny thing, we want to use Node.js, Rust, Go, Microservices, Cassandra, Hadoop, blablabla, blablabla, …

Operations want to use the same as they used yesterday, what they used last year, because it is proven, it works!

But, this is where Docker shines. Operations are satisfied because they only have to care about one thing. They have to support deploying containers. Developers are also happy. They can develop with whatever the fad of the day is and then just stick it into a container and throw it over the wall to Operations. Yippie ki-yay!

But, it does not end here. Since Operations are, usually, better than development when it comes to optimizing for production, they can help developers build optimized containers that can be used for local development. Not a bad situation at all.

If Docker is a contract between devs and devops, then Apcera's HCOS seals it in form of ITOps policies that make it  respected and implemented in an automated fashion