CATEGORY -CONTAINER SECURITYlinux-container-isolation-primitivesLinux Namespaces & Process Isolation

Linux Container Isolation Primitives (cgroups & namespaces)

Deep dive into the Linux kernel primitives that power containers: namespaces (PID, NET, MNT, IPC, UTS, USER) and control groups (cgroups v2).

Core Purpose & Operating Context

Inspect and audit the kernel-level boundaries that separate container processes from the underlying host.

01.

The 7 Linux Namespaces

Kernel mechanisms providing process isolation.

Inspect the namespace file descriptors for the current shell process

$ls -l /proc/$$/ns/

Create an isolated PID namespace and mount new procfs

$unshare --pid --fork --mount-proc /bin/bash

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User namespaces (USER) map container root (UID 0) to an unprivileged UID on the host, preventing host root compromise upon breakout.

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Control groups (cgroups v2) prevent denial-of-service by enforcing hard memory and CPU limits on container processes.