Cloud Engineer IL.txt

Cloud Engineer Practical Path

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Kubernetes - Multi-Container Pods

Name one multi-container pod pattern

	****sidecar****

How many containers does the Jupiter pod have?

	****4****(~kubectl get pods)

The Jupiter service exposes two pods a Python pod and PHP pod. They are exposed on two different ports, the Python pod is exposed on port 5000. What port is the PHP pod exposed on?

	****80****(~kubectl describe pods)

Use cURL to access the PHP pod of the Jupiter service at <cluster IP>:<pod_port>. Follow the instructions given in the output to obtain the token.

	****Long String*****(kubectl get pods -o wide)PHP=10.1.1.15:80 Python=10.1.1.15:5000

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Kubernetes - Pods and Services

A service routes traffic to pods based on selectors and which of the following?

	****Labels****

Viewing the pod’s YAML file, which port in the 'neptune' pod exposes the ‘nginx’ container internally?

	****Port 8127****(~cat neptune-pod.yaml)

Use kubectl to view the service. Which node port maps to the port in the previous question?

	****30001****(kubectl get service)(Each port has a mapping eg: 8127:30001

Use cURL to access the 'nginx' container. What is the token?
	****(~curl 10.152.183.151:8127)****

What is the original 'key: value' pair for the selector in the 'my-service' service’s YAML file?

	****run: find-neptune****(~cat service.yaml)(Do an ls 1st, see what files are there and pwd for which directory you are in)

What 'key: value' pair is the label assigned to the ‘my-nginx-app’ pod?

	****run: my-nginx-app****(same as above)

Which flag can be passed to kubectl's 'apply' command to specify that the resource configuration is contained in a file?

	****-f****(Need to use text editor like Vi or Vim as nano has C&P issues)

Using cURL, what is the token in the 'nginx2' container application within the 'my-nginx'app' pod?

	****kubectl describe pod my-nginx-app(This will give you details of pod and IP&Port numbers)
		kubectl edit -f service.yaml (Do an ls command and check for yaml files, service.yaml is master file to edit)
		cat service.yaml (Use this to varify changes)
			curl 10.152.183.68:8200 (use this command for specific IP&Port to connect to pod)


To exit Vim without saving changes:
	Switch to command mode by pressing the Esc key.
	Press : (colon) to open the prompt bar in the bottom left corner of the window.
	Type q! after the colon and hit Enter to exit without saving the changes.


Open a new or existing file with vim filename .
	Type i to switch into insert mode so that you can start editing the file.
	Enter or modify the text with your file.
	Once you're done, press the escape key Esc to get out of insert mode and back to command mode.
	Type :wq to save and exit your file.

==================================
Kubernetes - Volumes

Apply the deployment with kubectl apply -f deployment.yaml.

What is the requested capacity of the mariadb PV?

	****4gi****(~ls - cat deployment.yaml)

What is the storageclass name of the mariadb PVC?

	****local-storage****(Same as above)

What is the path of the PV on the host?

	****/mnt/mariadb****(Same as above)

In the directory from the previous question, how many sub-directories are there?

	****3****

Show contents of a database table using kubectl exec <pod name> -- mysql -uroot -e "use immersivelabs; select * from kubernetes limit 20;"

	 exec  mariadb-deployment-775544594-896d2 -- mysql -uroot -e "use immersivelabs; sele
ct * from kubernetes limit 20;" ****

What are the last six characters of the token value for #19 inside the 'Kubernetes' table?

	****56cd4e****

Delete the pod, and then wait for the replacement pod to spawn automatically.

 kubectl delete pod mariadb-deployment-775544594-ftqdm

What is the token value for #20 after pod deletion?

	****33171e****(~ get pods and query the db using the command above with the new pod name)

sudo rm -rf /mnt/mariadb
What is the error code returned for a database query?

	****1049****

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Kubernetes - Secrets

What encoding scheme is used by default when storing the values of secrets?

	****Base64****(Read briefing)

In a YAML file defining a secret, what field can be used in place of 'data' to enable secret values to be written in plaintext?

	****stringdata****

What field specifies the name of the secret to be mounted to a pod as a volume?

	****secret.secretName****

What kind of tokens containing credentials to grant API access are automatically mounted to pods upon their creation?

	****Service account tokens****

Use Kubectl to read the ‘creds’ secret in the ‘secret-ns’ namespace. In plaintext (decoded), what is the password?

	****24cd2a****(~kubectl edit secrets creds)

After successfully completing the previous task, a token will be printed on the command line, what is the token you receive?
Set the namespace context to 'secret-ns':
	kubectl config set-context --current --namespace=secret-ns

Create a file named my-first-secret.yaml and open it for editing:
touch my-first-secret.yaml
nano my-first-secret.yaml

In the editor, add the following YAML content to the my-first-secret.yaml file:
		apiVersion: v1
		kind: Secret
		metadata:
  		name: my-first-secret
		type: Opaque
		data:
  		user: S3ViaWU=  # Base64-encoded value of 'Kubie'
  		best-friend: RGF2ZQ==  # Base64-encoded value of 'Dave'

Save the changes and exit the editor.
Apply the secret configuration using the YAML file:
		kubectl apply -f my-first-secret.yaml

	****753bb6****

What token is printed by the 'mount-printer' pod? This can be viewed in the pod’s logs. Answer in plaintext.

	****


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Kubernetes - Workload Resources

In a ReplicaSet’s YAML file they create pods based on what?

	****pod template****

Which of these statements is true?

	****A PV Provisioner can assign storage to StatefulSet pods****

Query the ReplicaSets. How many asteroid pods are currently desired?

	****0****(~kubectl get replicasets)

What is the name of the image used in the asteroids deployment?

	****my-asteroid-image****(kubectl describe deployments)

What flag do you pass to 'kubectl scale' to indicate the number of pods you want to be running?

	****--replicas****

Increase the desired number of pods to ONE, wait until it is ready, and use cURL to access the asteroid container. What is the token?

	kubectl get replicasets(This will give you the name of the replicasets in your cluster)
		kubectl edit replicasets(This will open Vim, type 'I' for insert and navigate to replicas, under spec, change to '1' esc, :wq enter.
		 or kubectl scale deployment/asteroid-deployment --replicas=1
			kubectl describe pods(Search file for IP and Port, (2nd container)
				curl 10.1.102.1:8080(In this case IP and port are as described)
		Good job, you scaled the deployment and connected to the Nginx container!</p>
		<p>If your token does not appear, please wait until all pods are running.</p>
		<p>Your token is... 

There is a StatefulSet running on the cluster. Query its configuration. What label is given to the pods it creates?

	****run=nginx2****(~kubectl describe pod my-statefulset-1)

What flag can be passed when removing pods, to only delete those with a certain label?

	****--selector****

Return to the original terminal and delete the StatefulSet's pod

	kubectl delete pod my-statefulset-0
		kubectl get pods -w

Which pod is restarted last?

	****my-statefulset-2****

What was the status of the 'my-statefulset-0' pod when the scheduler began restarting the 'my-statefulset-1' pod?

	****running****

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Kubernetes - Namespaces and Network Policies

List the namespaces defined on the cluster.
How many namespaces with the prefix metrolio-* exist on the cluster

	****5****(~kubectl get namespaces)

Look at the service resources. Identify the nodePort used to expose pods with the label app=test-app.
What NodePort is the test-app-service available on?

	****32285****(~)

List the network policies that have been deployed to the cluster.
What is the name of the network policy that has been applied to the metrolio-dev-1 cluster?

	****metrolio-dev-1-deny-ingress****(~kubectl get networkpolicies --all-namespaces)

Create a new namespace called 'metrolio-new-namespace'. What is the output of the command you used?

	****namespace/metrolio-new-namespace created****(~kubectl create namespace metrolio-new-namespace)

Update the network policy found in the web-app-ingress.yaml file to permit access from the Desktop instance IP address to any pod with the label app=test-app. Using Chrome on the Desktop application, access the pod at http://<Kubernetes Node>:<nodePort>. What is the token provided?
	kubectl get all --all-namespaces
	




****

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: web-app-ingress
  namespace: metrolio-dev-1
spec:
  podSelector:
    matchLabels:
app: test-app
  ingress:
  - from:
    - ipBlock:
cidr: 11.106.12.251/32
ipBlock:
cidr: 192.168.235.196/32
    ports:
- protocol: TCP
port: 32285
protocol: TCP
port: 80
  policyTypes:
  - Ingress

kubectl apply -f web-app-ingress.yaml


apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: web-app-ingress
namespace: metrolio-dev-1
spec:
podSelector:
matchLabels:
app: test-app
ingress:
- from:
- ipBlock:
cidr: 11.96.255.240/24
ipBlock:
cidr: 10.102.101.203/24
ipBlock:
cidr: 0.0.0.0/32
ports:
- protocol: TCP
port: 32285
protocol: TCP
port: 80
policyTypes:
- Ingress