Docker VS VM
What is Docker?
Docker is a software development tool and a virtualization technology that makes it easy to develop, deploy, and manage applications by using containers. Container refers to a lightweight, stand-alone, executable package of a piece of software that contains all the libraries, configuration files, dependencies, and other necessary parts to operate the application.
What is a VM?
Virtual machines, on the other hand, are created to perform tasks that, if otherwise performed directly on the host environment, may prove to be risky. Virtual machines are isolated from the rest of the system; the software inside the virtual machine cannot tamper with the host computer. Therefore, implementing tasks such as accessing virus infected data and testing of operating systems are done using virtual machines.
Security
Virtual machines are stand-alone with their kernel and security features. Therefore, applications needing more privileges and security run on virtual machines.
On the flip side, providing root access to applications and running them with administrative premises is not recommended in the case of Docker containers because containers share the host kernel. The container technology has access to the kernel subsystems; as a result, a single infected application is capable of hacking the entire host system.
Portability
Virtual machines are isolated from their OS, and so, they are not ported across multiple platforms without incurring compatibility issues. At the development level, if an application is to be tested on different platforms, then Docker containers must be considered.
Docker containers packages are self-contained and can run applications in any environment, and since they don’t need a guest OS, they can be easily ported across different platforms. Docker containers can be easily deployed in servers since containers being lightweight can be started and stopped in very less time compared to virtual machines.
Performance
Virtual machines are more resource-intensive than Docker containers as the virtual machines need to load the entire OS to start. The lightweight architecture of Docker containers is less resource-intensive than virtual machines.
In the case of virtual machines, resources like CPU, memory, and I/O may not be allocated permanently to containers — unlike in the case of containers, where the resource usage with the load or traffic.
References:
