> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Solution Jobs and Cronjobs optional
> This article explains how to deploy a pod, create and update a Job, run jobs in parallel, and set up a CronJob in Kubernetes.
In this lesson, we will walk through a series of steps to deploy a pod, create and update a Job, run jobs in parallel, and set up a CronJob in Kubernetes. Follow along to see how each component is implemented.
─────────────────────────────
## 1. Deploying the Pod
We begin with a pod definition in the file **throw-dice-pod.yaml**. This pod runs a container using the `kodekloud/throw-dice` image. The container randomly generates a number between one and six. Here, a six indicates success while any other number signals failure. Our goal is to deploy the pod and review its logs to inspect the generated number.
First, list the file and preview its contents:
```bash theme={null}
root@controlplane ~ ➜ ls
throw-dice-pod.yaml
root@controlplane ~ ➜ cat throw-dice-pod.yaml
```
The contents of **throw-dice-pod.yaml** are as follows:
```yaml theme={null}
apiVersion: v1
kind: Pod
metadata:
name: throw-dice-pod
spec:
containers:
- image: kodekloud/throw-dice
name: throw-dice
restartPolicy: Never
```
Deploy the pod using:
```bash theme={null}
kubectl apply -f throw-dice-pod.yaml
```
Then, check the pod's status:
```bash theme={null}
kubectl get pod
```
If the pod status shows **Error**, it means the container generated a number other than six. Verify the result by inspecting the logs:
```bash theme={null}
kubectl logs throw-dice-pod
```
For example, an output like:
```plaintext theme={null}
4
```
indicates the container generated a four.
─────────────────────────────
## 2. Creating a Job to Measure Attempts
Next, we will create a Kubernetes Job named **throw-dice-job**. This Job uses the same pod definition (without extra commands) to determine how many attempts it takes to roll a six.
For further details, refer to the official Kubernetes Jobs documentation [here](https://kubernetes.io/docs/concepts/workloads/controllers/job/).
Create a file named **throw-dice-job.yaml** with the following content:
```yaml theme={null}
apiVersion: batch/v1
kind: Job
metadata:
name: throw-dice-job
spec:
template:
spec:
containers:
- name: throw-dice-job
image: kodekloud/throw-dice
restartPolicy: Never
backoffLimit: 25
```
Deploy the Job:
```bash theme={null}
kubectl apply -f throw-dice-job.yaml
```
Check its status with:
```bash theme={null}
kubectl get job
```
You might see an output like:
```plaintext theme={null}
NAME COMPLETIONS DURATION AGE
throw-dice-job 0/1 9s 9s
```
To review detailed pod events and status, describe the Job:
```bash theme={null}
kubectl describe job throw-dice-job
```
A sample output might display:
```plaintext theme={null}
Labels:
controller-uid: bbe00c05-eb94-4fed-a8b3-d064a2fd1dc5
job-name: throw-dice-job
Annotations:
batch.kubernetes.io/job-tracking:
Parallelism: 1
Completions: 1
Completion Mode: NonIndexed
Start Time: Wed, 03 Aug 2022 20:07:21 +0000
Completed At: Wed, 03 Aug 2022 20:07:39 +0000
Duration: 18s
Pods Statuses: 0 Active / 1 Succeeded / 3 Failed
...
```
In this example, the Job ran a total of 4 attempts (1 succeeded and 3 failed) until a pod succeeded in generating a six.
─────────────────────────────
## 3. Updating the Job for Multiple Completions
To modify the Job such that it continues running until it achieves three successful completions, follow these steps:
1. Delete the current Job:
```bash theme={null}
kubectl delete -f throw-dice-job.yaml
```
2. Update **throw-dice-job.yaml** to include the `completions` property. You can also increase the `backoffLimit` if more attempts are expected:
```yaml theme={null}
apiVersion: batch/v1
kind: Job
metadata:
name: throw-dice-job
spec:
template:
spec:
containers:
- name: throw-dice-job
image: kodekloud/throw-dice
restartPolicy: Never
backoffLimit: 25
completions: 3
```
3. Apply the updated Job:
```bash theme={null}
kubectl apply -f throw-dice-job.yaml
```
Monitor the Job’s status using:
```bash theme={null}
kubectl describe job throw-dice-job
```
A sample output might be:
```plaintext theme={null}
Labels:
controller-uid: 5b26aa1c-d92b-4634-85d3-ca1031f2ab0c
job-name: throw-dice-job
Parallelism: 1
Completions: 3
Start Time: Wed, 03 Aug 2022 20:10:23 +0000
Completed At: Wed, 03 Aug 2022 20:10:37 +0000
Duration: 14s
Pods Statuses: 0 Active / 3 Succeeded / 1 Failed
...
```
This output indicates that the Job took 4 attempts (three successful and one failed) to complete.
─────────────────────────────
## 4. Running Jobs in Parallel
To run the Job in parallel instead of sequentially, add the `parallelism` property to the definition. If necessary, delete the existing Job and update **throw-dice-job.yaml** as follows:
```yaml theme={null}
apiVersion: batch/v1
kind: Job
metadata:
name: throw-dice-job
spec:
parallelism: 3
completions: 3
template:
spec:
containers:
- name: throw-dice-job
image: kodekloud/throw-dice
restartPolicy: Never
backoffLimit: 35
```
Deploy the updated Job:
```bash theme={null}
kubectl apply -f throw-dice-job.yaml
```
You can describe the Job to verify that pods are now running in parallel and that you achieve three successful completions more quickly.
─────────────────────────────
## 5. Creating a CronJob
The final task is to create a CronJob that executes the job daily at 21:30. Create a file named **throw-dice-cronjob.yaml** with the following definition:
```yaml theme={null}
apiVersion: batch/v1
kind: CronJob
metadata:
name: throw-dice-cron-job
spec:
schedule: "30 21 * * *"
jobTemplate:
spec:
template:
spec:
containers:
- name: throw-dice
image: kodekloud/throw-dice
restartPolicy: Never
```
Ensure that the restart policy is specified as **Never** (with a capital “N”). Using "never" (all lowercase) will result in an error.
Deploy the CronJob:
```bash theme={null}
kubectl apply -f throw-dice-cronjob.yaml
```
A successful deployment might return:
```bash theme={null}
cronjob.batch/throw-dice-cron-job created
```
─────────────────────────────
## Conclusion
In this lesson, we covered how to:
* Deploy a pod that performs a dice-rolling operation.
* Create a Job to measure the number of attempts required for a successful roll.
* Update the Job to require multiple completions.
* Configure the Job to run in parallel.
* Schedule the Job using a CronJob to run daily at a specified time.
These steps provide a comprehensive look at managing Kubernetes Jobs and CronJobs. Enjoy experimenting with these configurations in your Kubernetes environment!
For more detailed information on Kubernetes components, visit the following resources:
* [Kubernetes Documentation](https://kubernetes.io/docs/)
* [Kubernetes Basics](https://kubernetes.io/docs/concepts/overview/what-is-kubernetes/)