PodIP

PodIP is the IP address assigned to an individual Pod in a container orchestration environment such as Kubernetes. It identifies the Pod on the cluster network and serves as the primary address for direct Pod-to-Pod communication within the cluster.

Assignment and scope: Each Pod receives a unique IP from the cluster's Pod network CIDR via the container network interface provided by the CNI plugin. The IP is allocated when the Pod is created and remains tied to that Pod for the Pod’s lifetime. If a Pod is terminated and recreated, it may receive a new PodIP.

Networking semantics: All containers within a Pod share the same Pod IP and port namespace, allowing them to communicate with other Pods using that IP. Pod IPs are routable within the cluster network but are not typically reachable from outside the cluster without a Service, Ingress, or similar exposure mechanism. Pod IPs are not intended to be stable across Pod restarts or rescheduling.

Lifecycle and management: The PodIP is released when the Pod terminates and can be reassigned to future Pods. The stability of IPs is limited by the cluster’s networking and CNI provider. Network policies may restrict which Pods can communicate with a given Pod IP.

Practical notes: In normal operation, applications reach a Pod via a Service with a stable DNS name; this abstracts the Pod IP and protects against Pod replacement. Pod IP visibility depends on the underlying CNI and cluster configuration, and may vary between environments.