What is Kubernetes Pod Lifecycle Conditions?

Question

Accepted Answer

**Conditions** — status indicators for Pod state.

```yaml
apiVersion: v1
kind: Pod
metadata:
  name: my-pod
spec:
  containers:
  - name: app
    image: nginx:latest
    startupProbe:
      httpGet:
        path: /healthz
        port: 8080
      failureThreshold: 30
      periodSeconds: 10
    readinessProbe:
      httpGet:
        path: /ready
        port: 8080
      initialDelaySeconds: 5
      periodSeconds: 10
    livenessProbe:
      httpGet:
        path: /healthz
        port: 8080
      initialDelaySeconds: 15
      periodSeconds: 20
```

```bash
# Check Pod conditions
kubectl get pod my-pod -o jsonpath='{.status.conditions}' | jq

# Check specific condition
kubectl get pod my-pod -o jsonpath='{.status.conditions[?(@.type=="Ready")].status}'
kubectl get pod my-pod -o jsonpath='{.status.conditions[?(@.type=="PodScheduled")].status}'
kubectl get pod my-pod -o jsonpath='{.status.conditions[?(@.type=="ContainersReady")].status}'
kubectl get pod my-pod -o jsonpath='{.status.conditions[?(@.type=="Initialized")].status}'

# Check all conditions
kubectl get pod my-pod -o json | jq '.status.conditions[] | {type: .type, status: .status, reason: .reason, message: .message}'

# Watch condition changes
kubectl get pod my-pod -w
kubectl get events --field-selector involvedObject.name=my-pod

# Check container status
kubectl get pod my-pod -o jsonpath='{.status.containerStatuses}' | jq
```

**Conditions:**
- PodScheduled: assigned to a node.
- Initialized: init containers completed.
- ContainersReady: all containers ready.
- Ready: Pod can serve requests.

**Status Values:**
- True: condition met.
- False: condition not met.
- Unknown: condition unknown.

DevOps: What is Kubernetes Pod Lifecycle Conditions?