sidecar-container

 apiVersion: v1
kind: Pod
metadata:
  name: my-pod
spec:
  containers:
  - name: main-container
    image: busybox
    command: ["sh", "-c", "echo 'Main process running'; sleep 30"]
  - name: sidecar-container
    image: busybox
    command: ["sh", "-c", "while true; do sleep 3600; done"]

Sidecar, Kubernetes Sidecar Containers, Sidecar (Kubernetes), Sidecar container