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Solution:

Solution:

To update the nginxsvc service to serve on port 5050, you will need to edit the service's definition yaml file. You can use the kubectl edit command to edit the service in place.

kubectl edit svc nginxsvc

This will open the service definition yaml file in your default editor. Change the targetPort of the service to 5050 and save the file.

To add an HAproxy container named haproxy bound to port 90 to the poller pod, you will need to edit the pod's definition yaml file located at /opt/KDMC00101/poller.yaml.

You can add a new container to the pod's definition yaml file, with the following configuration:

containers:

- name: haproxy

image: haproxy

ports:

- containerPort: 90

volumeMounts:

- name: haproxy-config

mountPath: /usr/local/etc/haproxy/haproxy.cfg

subPath: haproxy.cfg

args: ["haproxy", "-f", "/usr/local/etc/haproxy/haproxy.cfg"]

This will add the HAproxy container to the pod and configure it to listen on port 90. It will also mount the ConfigMap haproxy-config to the container, so that haproxy.cfg is available at /usr/local/etc/haproxy/haproxy.cfg.

To inject the configuration located at /opt/KDMC00101/haproxy.cfg to the container, you will need to create a ConfigMap using the following command:

kubectl create configmap haproxy-config --from-file=/opt/KDMC00101/haproxy.cfg

You will also need to update the args of the poller container so that it connects to localhost instead of nginxsvc. You can do this by editing the pod's definition yaml file and changing the args field to args: ["poller","--host=localhost"].

Once you have made these changes, you can deploy the updated pod to the cluster by running the following command:

kubectl apply -f /opt/KDMC00101/poller.yaml

This will deploy the enhanced pod with the HAproxy container to the cluster. The HAproxy container will listen on port 90 and proxy connections to the nginxsvc service on port 5050. The poller container will connect to localhost instead of nginxsvc, so that the connection is correctly proxied to the new service endpoint.

Please note that, this is a basic example and you may need to tweak the haproxy.cfg file and the args based on your use case.

To find the broken pod and store its name and namespace to /opt/KDOB00401/broken.txt, you can use the kubectl get pods command and filter the output by the status of the pod.

kubectl get pods --field-selector=status.phase=Failed -o jsonpath='{.items[*].metadata.namespace}/{.items[*].metadata.name}' > /opt/KDOB00401/broken.txt

This command will list all pods with a status of Failed and output their names and namespaces in the format /. The output is then written to the /opt/KDOB00401/broken.txt file.

To store the associated error events to a file /opt/KDOB00401/error.txt, you can use the kubectl describe command to retrieve detailed information about the pod, and the grep command to filter the output for error events.

kubectl describe pods --namespace | grep -i error -B5 -A5 > /opt/KDOB00401/error.txt

Replace and with the name and namespace of the broken pod you found in the previous step.

This command will output detailed information about the pod, including error events. The grep command filters the output for lines containing "error" and also prints 5 lines before and after the match.

To fix the issue, you need to analyze the error events and find the root cause of the issue.

It could be that the application inside the pod is not running, the container image is not available, the pod has not enough resources, or the liveness probe configuration is incorrect.

Once you have identified the cause, you can take appropriate action, such as restarting the application, updating the container image, increasing the resources, or modifying the liveness probe configuration.

After fixing the issue, you can use the kubectl get pods command to check the status of the pod and ensure

Solution:

To have Kubernetes automatically restart a pod when an endpoint returns an HTTP 500 on the /healthz endpoint, you will need to configure liveness and readiness probes on the pod.

First, you will need to create a livenessProbe and a readinessProbe in the pod's definition yaml file. The livenessProbe will check the /healthz endpoint, and if it returns an HTTP 500, the pod will be restarted. The readinessProbe will check the /started endpoint, and if it returns an HTTP 500, the pod will not receive traffic.

Here's an example of how you can configure the liveness and readiness probes in the pod definition yaml file:

apiVersion: v1

kind: Pod

metadata:

name: probe-pod

spec:

containers:

- name: probe-pod

image:

ports:

- containerPort: 8080

livenessProbe:

httpGet:

path: /healthz

port: 8080

initialDelaySeconds: 15

periodSeconds: 10

failureThreshold: 3

readinessProbe:

httpGet:

path: /started

port: 8080

initialDelaySeconds: 15

periodSeconds: 10

failureThreshold: 3

The httpGet specifies the endpoint to check and the port to use. The initialDelaySeconds is the amount of time the pod will wait before starting the probe. periodSeconds is the amount of time between each probe check, and the failureThreshold is the number of failed probes before the pod is considered unresponsive.

You can use kubectl to create the pod by running the following command:

kubectl apply -f .yaml

Once the pod is created, Kubernetes will start monitoring it using the configured liveness and readiness probes. If the /healthz endpoint returns an HTTP 500, the pod will be restarted. If the /started endpoint returns an HTTP 500, the pod will not receive traffic.

Please note that if the failure threshold is set to 3, it means that if the probe fails 3 times consecutively it will be considered as a failure.

The above configuration assumes that the application is running on port 8080 and the endpoints are available on the same port.

Solution:

Solution:

create deploy hello-deploy --image=nginx --dry-run=client -o yaml > hello-deploy.yaml

Update deployment image to nginx:1.17.4:                                       kubectl set image deploy/hello-deploy nginx=nginx:1.17.4

Solution:

Solution:

To deploy the counter pod to the cluster using the provided YAML spec file, you can use the kubectl apply command. The apply command creates and updates resources in a cluster.

kubectl apply -f /opt/KDOB00201/counter.yaml

This command will create the pod in the cluster. You can use the kubectl get pods command to check the status of the pod and ensure that it is running.

kubectl get pods

To retrieve all currently available application logs from the running pod and store them in the file /opt/KDOB0020l/log_Output.txt, you can use the kubectl logs command. The logs command retrieves logs from a container in a pod.

kubectl logs -f > /opt/KDOB0020l/log_Output.txt

Replace with the name of the pod.

You can also use -f option to stream the logs.

kubectl logs -f > /opt/KDOB0020l/log_Output.txt &

This command will retrieve the logs from the pod and write them to the /opt/KDOB0020l/log_Output.txt file.

Please note that the above command will retrieve all logs from the pod, including previous logs. If you want to retrieve only the new logs that are generated after running the command, you can add the --since flag to the kubectl logs command and specify a duration, for example --since=24h for logs generated in the last 24 hours.

Also, please note that, if the pod has multiple containers, you need to specify the container name using -c option.

kubectl logs -f -c > /opt/KDOB0020l/log_Output.txt

The above command will redirect the logs of the specified container to the file.