How is a docker container different from a virtual machine?

Docker is container based technology and containers are just user space of the operating system. In Docker, the containers running share the host OS kernel. A Virtual Machine, on the other hand, is not based on container technology. They are made up of user space plus kernel space of an operating system.

What are containers and how are they different than virtualization?

Virtualization enables you to run multiple operating systems on the hardware of a single physical server, while containerization enables you to deploy multiple applications using the same operating system on a single virtual machine or server.

What are advantages of containers versus virtual machines?

Their containers perform faster than VMs, can be spun up and down a lot faster, and have better access to system resources. The main benefit of the container is their small size and the ability to run hundreds or even thousands on a server vs. a few dozen virtual machines.

Do not use docker If you need to use different operating systems or kernels?

No, it does not. Docker uses containerisation as a core technology, which relies on the concept of sharing a kernel between containers. If one Docker image relies on a Windows kernel and another relies on a Linux kernel, you cannot run those two images on the same OS.

Why do docker containers need an OS?

Unlike VMs, containers do not have an OS within it. They simply share the underlying kernel with the other containers. Docker containers can actually run within VMs. This allows teams to containerize each service and run multiple Docker containers per vm.

What is a container virtual machine?

With containers, instead of virtualizing the underlying computer like a VM, just the OS is virtualized. Containers sit on top of a physical server and its host OS—typically Linux or Windows. Each container shares the host OS kernel and, usually, the binaries and libraries, too.

What are advantages of containers?

Benefits of containers Containers require less system resources than traditional or hardware virtual machine environments because they don’t include operating system images. Applications running in containers can be deployed easily to multiple different operating systems and hardware platforms.