InvalidApplicationUID

This message occurs when a workload is running as User ID (UID) 1337. Application pods should not run as user ID (UID) 1337 because the istio-proxy container runs as UID 1337. Running your application containers using the same UID would result in conflicts with its iptables configurations.

An example

Consider a Deployment with securityContext.runAsUser running either at Pod level or at container level using UID 1337:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: deploy-con-sec-uid
  labels:
    app: helloworld
    version: v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
      version: v1
  template:
    metadata:
      labels:
        app: helloworld
        version: v1
    spec:
      securityContext:
        runAsUser: 1337
      containers:
      - name: helloworld
        image: docker.io/istio/examples-helloworld-v1
        securityContext:
          runAsUser: 1337
        resources:
          requests:
            cpu: "100m"
        imagePullPolicy: IfNotPresent #Always
        ports:
        - containerPort: 5000

How to resolve

Because the User ID (UID) 1337 is reserved for the sidecar proxy, you can use a different User ID (UID) such as 1338 for your workload.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: deploy-con-sec-uid
  labels:
    app: helloworld
    version: v1
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
      version: v1
  template:
    metadata:
      labels:
        app: helloworld
        version: v1
    spec:
      securityContext:
        runAsUser: 1338
      containers:
      - name: helloworld
        image: docker.io/istio/examples-helloworld-v1
        securityContext:
          runAsUser: 1338
        resources:
          requests:
            cpu: "100m"
        imagePullPolicy: IfNotPresent #Always
        ports:
        - containerPort: 5000