Pod terminated with reason Error and Exit Code: 1 - docker

Question

I have Question on pod termination on using image: kodekloud/throw-dice
pod-defintion.yml
apiVersion: v1
kind: Pod
metadata:
name: throw-dice-pod
spec:
containers:
- image: kodekloud/throw-dice
name: throw-dice
restartPolicy: Never
I have checked the steps in DockerFile . It runs throw-dice.sh which randomly returns number in between 1 - 6.
let's consider first time container return 3, so how below pod is terminated ? where is the condition defined in the pod level it suppose to terminate if script return number is !6.
Below steps were performed to execute pod-definition.yml
master $ kubectl create -f /root/throw-dice-pod.yaml
pod/throw-dice-pod created
master $ kubectl get pods
NAME READY STATUS RESTARTS AGE
throw-dice-pod 0/1 ContainerCreating 0 9s
master $ kubectl get pods
NAME READY STATUS RESTARTS AGE
throw-dice-pod 0/1 Error 0 12s
master $ kubectl describe pod throw-dice-pod
Name: throw-dice-pod
Namespace: default
Priority: 0
Node: node01/172.17.0.83
Start Time: Sat, 16 May 2020 11:20:01 +0000
Labels: <none>
Annotations: <none>
Status: Failed
IP: 10.88.0.4
IPs:
IP: 10.88.0.4
Containers:
throw-dice:
Container ID: docker://4560c794b58cf8f3e3fad691b2292e37db4e84e20c9286321f026d1735272b5f
Image: kodekloud/throw-dice
Image ID: docker-pullable://kodekloud/throw-dice#sha256:9c70a0f907b99293885a9591b6162e9ec89e127937626a97ca7f9f6be2d98b01
Port: <none>
Host Port: <none>
State: Terminated
Reason: Error
Exit Code: 1
Started: Sat, 16 May 2020 11:20:10 +0000
Finished: Sat, 16 May 2020 11:20:10 +0000
Ready: False
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-nr5kl (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
default-token-nr5kl:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-nr5kl
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled <unknown> default-scheduler Successfully assigned default/throw-dice-pod to node01
Normal Pulling 21s kubelet, node01 Pulling image "kodekloud/throw-dice"
Normal Pulled 19s kubelet, node01 Successfully pulled image "kodekloud/throw-dice"
Normal Created 19s kubelet, node01 Created container throw-dice
Normal Started 18s kubelet, node01 Started container throw-dice
master $ kubectl logs throw-dice-pod
2

Answer 1

The dockerfile has ENTRYPOINT sh throw-dice.sh which means execute the script and then the container terminates automatically. If you want the container to keep running you need to start a long running process for example a java process ENTRYPOINT ["java", "-jar", "/whatever/your.jar"]

Answer 2

Exit code 1 here is set by the application.
Take a look into throw-dice.sh. We see that the application shuffling exit code between 0,1,2.
The exit code is always equal to shuffling result above.
If the exit code is 0, 6 is logged.
If the exit code is 1 or 2, result from shuffling integer from 1-5 is logged
So in your case, exit code from shuffling is 1 and shuffling result for log is 2. And exit code 1 from application is considered as Error reason for Kubernetes.