What Linux namespace is shared by default by containers running within a Kubernetes Pod?

Containers share the Host Network namespace only if explicitly configured with `hostNetwork: true`, which is not the default and generally discouraged for security reasons.

By default, all containers within a single Kubernetes Pod share the same Network namespace. This means they share the same IP address, network ports, and can communicate with each other via localhost, facilitating sidecar patterns and inter-container communication.

Containers within a Pod typically run in separate Process ID (PID) namespaces, meaning they have their own independent view of processes, although they can be configured to share one.

Process Name is not a standard Linux namespace that can be shared or isolated; Linux namespaces primarily include PID, Network, Mount, UTS, IPC, and User.