26.3. Introducing namespaces
Namespaces create separate spaces for organizing and identifying software objects. This keeps them from affecting each other. As a result, each software object contains its own set of resources, for example, a mount point, a network device, or a hostname, even though they are sharing the same system.
One of the most common technologies that use namespaces are containers.
Changes to a particular global resource are visible only to processes in that namespace and do not affect the rest of the system or other namespaces.
To inspect which namespaces a process is a member of, you can check the symbolic links in the /proc/<PID>/ns/ directory.
| Namespace | Isolates |
|---|---|
| Mount | Mount points |
| UTS | Hostname and NIS domain name |
| IPC | System V IPC, POSIX message queues |
| PID | Process IDs |
| Network | Network devices, stacks, ports, etc |
| User | User and group IDs |
| Control groups | Control group root directory |
See namespaces(7) and cgroup_namespaces(7) man pages on your system for more information.