Skip to content

Docker container isolation

Docker container isolation refers to the mechanism by which Docker containers ensure that running processes are restricted from the host system and from each other. Unlike traditional virtual machines, containers achieve this primarily through the use of Linux Namespaces rather than full hardware virtualization^[400-devops-06-kubernetes-k8s-paas-readme.md].

Core Technology: Namespaces

The primary technology enabling container isolation is the Linux Kernel feature known as Namespaces^[400-devops-06-kubernetes-k8s-paas-readme.md]. These wrappers allow the host system to partition resources—such as process IDs, network stacks, and file systems—so that a process inside a container has a restricted view of the system, distinct from the host and other containers^[400-devops-06-kubernetes-k8s-paas-readme.md].

Comparison with Virtual Machines

It is important to distinguish the isolation model of containers from that of virtual machines. Virtual Machines (VMs) simulate a complete hardware stack and run a full guest operating system, whereas Docker containers share the host system's kernel and isolate processes at the operating system level^[400-devops-06-kubernetes-k8s-paas-readme.md]. This makes containers significantly more lightweight and faster to start than VMs^[400-devops-06-kubernetes-k8s-paas-readme.md].

Sources

^[400-devops-06-kubernetes-k8s-paas-readme.md]