What is Network Namespace?

Network namespaces create completely separate networking environments within a single Linux host. Each namespace has its own network interfaces, IP addresses, routing table, firewall rules, and port space. Processes in different namespaces cannot see each other's network configuration. This is foundational to container networking — Docker and Kubernetes use network namespaces to give each container its own network stack. Virtual Ethernet (veth) pairs connect namespaces, while bridge devices enable communication between them. Administrators can create and manage namespaces with ip netns commands.