Lesson 12.5: Practice Exam Set 2
Question 1
Create a new pod called admin-pod with image busybox . allow the pod to set system time . the container should sleep for 3200 seconds. The pod should be in production namespace
[root@master practice-2]# kubectl run admin-pod --image=busybox:latest --command sleep 3200 --dry-run=client -o yaml > 1.yml
[root@master practice-2]# cat 1.yml
apiVersion: v1
kind: Pod
metadata:
labels:
run: admin-pod
name: admin-pod
namespace: production
spec:
containers:
- command:
- sleep
- "3200"
image: busybox:latest
name: admin-pod
securityContext:
capabilities:
add: ["SYS_TIME"]
[root@master practice-2]# kubectl apply -f 1.yml
pod/admin-pod created
[root@master practice-2]# kubectl get pods -n production
NAME READY STATUS RESTARTS AGE
admin-pod 1/1 Running 0 12sQuestion 2
A KubeConfig file called config has been created in ~/.kube/config. There is something wrong with the configuration. Troubeshoot and fix it.
View your existing configuration with the command kubectl config view
[root@master practice-2]# kubectl config view
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://127.0.0.1:46411
name: kind-cka-cluster1
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://127.0.0.1:45421
name: kind-dev
contexts:
- context:
cluster: kind-cka-cluster1
user: kind-cka-cluster1
name: kind-cka-cluster1
- context:
cluster: kind-dev
user: kind-dev
name: kind-dev
current-context: kind-dev
kind: Config
preferences: {}
users:
- name: kind-cka-cluster1
user:
client-certificate-data: DATA+OMITTED
client-key-data: DATA+OMITTED
- name: kind-dev
user:
client-certificate-data: DATA+OMITTED
client-key-data: DATA+OMITTEDThe certifications will not have issue, the issue will lie in the server url/port. Check with the above configuration and fix in the config file provided. Edit with vim and save the changes, then view the config again with kubectl config view.
[root@master practice-2]# cat ~/.kube/config
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: ...
server: https://127.0.0.1:46411
name: kind-cka-cluster1
- cluster:
certificate-authority-data: ...
server: https://127.0.0.1:45421
name: kind-dev
contexts:
- context:
cluster: kind-cka-cluster1
user: kind-cka-cluster1
name: kind-cka-cluster1
- context:
cluster: kind-dev
user: kind-dev
name: kind-dev
current-context: kind-dev
kind: Config
preferences: {}
users:
- name: kind-cka-cluster1
user:
client-certificate-data: ...
client-key-data: ...
- name: kind-dev
user:
client-certificate-data: ...
client-key-data: ...Question 3
Create a new deployment called web-proj-268, with image nginx:1.16 and 1 replica. Next upgrade the new deployment to version 1.17 using rolling update. Make sure that the version upgrade is recorded in the resource annotation.
# version nginx:1.16
[root@master practice-2]# vim q3.yml
[root@master practice-2]# cat q3.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: web-proj-268
name: web-proj-268
spec:
replicas: 1
selector:
matchLabels:
app: web-proj-268
template:
metadata:
labels:
app: web-proj-268
annotations:
kubernetes.io/change-cause: "Deployment of nginx version 1.16"
spec:
containers:
- image: nginx:1.16
name: nginx
[root@master practice-2]# kubectl apply -f q3.yml
deployment.apps/web-proj-268 created
[root@master practice-2]# kubectl rollout history deploy web-proj-268
deployment.apps/web-proj-268
REVISION CHANGE-CAUSE
1 Deployment of nginx version 1.16
# Version nginx:1.17
[root@master practice-2]# vim q3.yml
[root@master practice-2]# cat q3.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: web-proj-268
name: web-proj-268
spec:
replicas: 1
selector:
matchLabels:
app: web-proj-268
template:
metadata:
labels:
app: web-proj-268
annotations:
kubernetes.io/change-cause: "Deployment of nginx version 1.17"
spec:
containers:
- image: nginx:1.17
name: nginx
[root@master practice-2]# kubectl apply -f q3.yml
deployment.apps/web-proj-268 configured
[root@master practice-2]# kubectl rollout history deploy web-proj-268
deployment.apps/web-proj-268
REVISION CHANGE-CAUSE
1 Deployment of nginx version 1.16
2 Deployment of nginx version 1.17
# version nginx:latest
[root@master practice-2]# vim q3.yml
[root@master practice-2]# cat q3.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: web-proj-268
name: web-proj-268
spec:
replicas: 1
selector:
matchLabels:
app: web-proj-268
template:
metadata:
labels:
app: web-proj-268
annotations:
kubernetes.io/change-cause: "Deployment of nginx version latest"
spec:
containers:
- image: nginx:latest
name: nginx
[root@master practice-2]# kubectl apply -f q3.yml
deployment.apps/web-proj-268 configured
[root@master practice-2]# kubectl rollout history deploy web-proj-268
deployment.apps/web-proj-268
REVISION CHANGE-CAUSE
1 Deployment of nginx version 1.16
2 Deployment of nginx version 1.17
3 Deployment of nginx version latest
# Undo to version 1.16 --to-revision=1
[root@master practice-2]# kubectl rollout undo deployment web-proj-268 --to-revision=1
deployment.apps/web-proj-268 rolled back
[root@master practice-2]# kubectl get pods
NAME READY STATUS RESTARTS AGE
web-proj-268-78c5764bc8-ldvwh 1/1 Running 0 7s
[root@master practice-2]# kubectl describe pod web-proj-268-78c5764bc8-ldvwh | grep -i image
Image: nginx:1.16
# Undo to version 1.17 --to-revision=2
[root@master practice-2]# kubectl rollout undo deploy web-proj-268 --to-revision=2
deployment.apps/web-proj-268 rolled back
[root@master practice-2]# kubectl get pods
NAME READY STATUS RESTARTS AGE
web-proj-268-7b99bdd4f4-fdn5d 1/1 Running 0 5s
[root@master practice-2]# kubectl describe pod web-proj-268-7b99bdd4f4-fdn5d | grep -i image:
Image: nginx:1.17
# undo to version latest --to-revision=3
[root@master practice-2]# kubectl rollout undo deploy web-proj-268 --to-revision=3
deployment.apps/web-proj-268 rolled back
[root@master practice-2]# kubectl get pods
NAME READY STATUS RESTARTS AGE
web-proj-268-6c9ff76bc8-zncv4 1/1 Running 0 3s
[root@master practice-2]# kubectl describe pod web-proj-268-6c9ff76bc8-zncv4 | grep -i image:
Image: nginx:latest
[root@master practice-2]# kubectl rollout history deploy web-proj-268
deployment.apps/web-proj-268
REVISION CHANGE-CAUSE
4 Deployment of nginx version 1.16
5 Deployment of nginx version 1.17
6 Deployment of nginx version latestQuestion 4
Create a new deployment called web-003. Scale the deployment to 3 replicas. Make sure the desired number of pod is always running.
- This question is based on troubleshooting.
[root@master practice-2]# kubectl create deployment web-003 --image=nginx:latest --replicas=3 --dry-run=client -o yaml > q4.yml
[root@master practice-2]# vim q4.yml
[root@master practice-2]# cat q4.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: web-003
name: web-003
spec:
replicas: 3
selector:
matchLabels:
app: web-003
template:
metadata:
labels:
app: web-003
spec:
containers:
- image: nginx:latest
name: nginx
[root@master practice-2]# kubectl apply -f q4.yml
deployment.apps/web-003 created
[root@master practice-2]# kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
web-003 0/3 0 0 6s
[root@master practice-2]# kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
web-003 0/3 0 0 12s- You can see that the deployment is not running, so we need to check the
kube-systemnamespace pods. - Here, we can see that
kube-controller-manager-dev-control-planeis inCrashLoopBackOffstatus. - So we check the static manifest files for errors.
[root@master practice-2]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-77969b7d87-gh6pf 1/1 Running 7 (15h ago) 4d17h
calico-node-5qxtf 1/1 Running 7 (15h ago) 10d
calico-node-glgmq 1/1 Running 6 (15h ago) 10d
calico-node-pjhtn 1/1 Running 8 (15h ago) 10d
coredns-668d6bf9bc-hb87b 1/1 Running 1 (15h ago) 4d17h
coredns-668d6bf9bc-xrljm 1/1 Running 4 (15h ago) 10d
etcd-dev-control-plane 1/1 Running 0 15h
kube-apiserver-dev-control-plane 1/1 Running 0 15h
kube-controller-manager-dev-control-plane 0/1 CrashLoopBackOff 5 (50s ago) 4m2s
kube-proxy-2dqnc 1/1 Running 5 (15h ago) 10d
kube-proxy-c227m 1/1 Running 5 (15h ago) 10d
kube-proxy-fpj9c 1/1 Running 5 (15h ago) 10d
kube-scheduler-dev-control-plane 1/1 Running 1 (15h ago) 10d
metrics-server-55d46898f-8bvpr 1/1 Running 2 (15h ago) 3d23h
[root@master practice-2]# kubectl describe pod kube-controller-manager-dev-control-plane -n kube-system
State: Waiting
Reason: CrashLoopBackOff
Last State: Terminated
Reason: StartError
Message: failed to create containerd task: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: error during container init: exec: "kube-controller-man": executable file not found in $PATH
# Troubleshoot the manifest file
[root@master practice-2]# docker exec -it dev-control-plane bash
root@dev-control-plane:/# cd /etc/kubernetes/manifests/
root@dev-control-plane:/etc/kubernetes/manifests# ls
etcd.yaml kube-apiserver.yaml kube-controller-manager.yaml kube-scheduler.yaml
root@dev-control-plane:/etc/kubernetes/manifests# vim kube-controller-manager.yaml
# Change the command
spec:
containers:
- command:
- kube-controller-manager # Fix this part to kube-controller-manager from kube-controller-man# Check the pod status
[root@master practice-2]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-77969b7d87-gh6pf 1/1 Running 7 (15h ago) 4d17h
calico-node-5qxtf 1/1 Running 7 (15h ago) 10d
calico-node-glgmq 1/1 Running 6 (15h ago) 10d
calico-node-pjhtn 1/1 Running 8 (15h ago) 10d
coredns-668d6bf9bc-hb87b 1/1 Running 1 (15h ago) 4d17h
coredns-668d6bf9bc-xrljm 1/1 Running 4 (15h ago) 10d
etcd-dev-control-plane 1/1 Running 0 15h
kube-apiserver-dev-control-plane 1/1 Running 0 15h
kube-controller-manager-dev-control-plane 1/1 Running 0 80s
kube-proxy-2dqnc 1/1 Running 5 (15h ago) 10d
kube-proxy-c227m 1/1 Running 5 (15h ago) 10d
kube-proxy-fpj9c 1/1 Running 5 (15h ago) 10d
kube-scheduler-dev-control-plane 1/1 Running 1 (15h ago) 10d
metrics-server-55d46898f-8bvpr 1/1 Running 2 (15h ago) 3d23h
# The deployment and pod is running successfully
[root@master practice-2]# kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
web-003 3/3 3 3 11m
[root@master practice-2]# kubectl get pods
NAME READY STATUS RESTARTS AGE
web-003-9bc9fc76b-6445s 1/1 Running 0 99s
web-003-9bc9fc76b-j4gxj 1/1 Running 0 99s
web-003-9bc9fc76b-r5fvq 1/1 Running 0 99sQuestion 5
Upgrade the Cluster (Master and worker node) from v1.32.1 to v1.32.0. Make sure you drain both node and make it available after upgrade.
Set the node named controlplane as unavailable and reschedule all the pods running on it.
controlplane:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
controlplane Ready control-plane 12d v1.32.1
node01 Ready <none> 12d v1.32.1
controlplane:~$ kubectl drain controlplane --ignore-daemonsets
controlplane:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
controlplane Ready,SchedulingDisabled control-plane 12d v1.32.1
node01 Ready <none> 12d v1.32.1controlplane:~$ apt-get install kubeadm=1.32.0-1.1
controlplane:~$ kubeadm upgrade apply v1.32.0
[upgrade] SUCCESS! A control plane node of your cluster was upgraded to "v1.32.1".
controlplane:~$ apt-get install kubelet=1.32.0-1.1 kubectl=1.32.0-1.1
controlplane:~$ systemctl restart kubeletcontrolplane:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
controlplane Ready control-plane,SchedulingDisabled 12d v1.32.0
node01 Ready <none> 12d v1.32.1
controlplane:~$ kubectl uncordon controlplane
controlplane:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
controlplane Ready control-plane 12d v1.32.0
node01 Ready <none> 12d v1.32.1controlplane:~$ kubectl drain node01 --ignore-daemonsets
controlplane:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
controlplane Ready control-plane 12d v1.32.0
node01 Ready,SchedulingDisabled <none> 12d v1.32.1
controlplane:~$ ssh node01
node01:~$ apt-get install kubeadm=1.32.0-1.1
node01:~$ kubeadm upgrade node
node01:~$ apt-get install kubelet=1.32.0-1.1 kubectl=1.32.0-1.1
node01:~$ systemctl restart kubelet
node01:~$ exit
logout
Connection to node01 closed.
controlplane:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
controlplane Ready control-plane 12d v1.32.0
node01 Ready,SchedulingDisabled <none> 12d v1.32.0
controlplane:~$ kubectl uncordon node01
node/node01 uncordoned
controlplane:~$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
controlplane Ready control-plane 12d v1.32.0
node01 Ready <none> 12d v1.32.0Question 6
Deploy a web-load-5461 pod using the image nginx:1.17 with the labels set to tier=web
- Weightage : 4% (simple)
[root@master practice-2]# kubectl run web-load-5461 --image=nginx:1.17 --labels tier=web --dry-run=client -o yaml > q6.yml
[root@master practice-2]# vim q6.yml
[root@master practice-2]# cat q6.yml
apiVersion: v1
kind: Pod
metadata:
labels:
tier: web
name: web-load-5461
spec:
containers:
- image: nginx:1.17
name: web-load-5461
[root@master practice-2]# kubectl apply -f q6.yml
pod/web-load-5461 created
[root@master practice-2]# kubectl get pods --show-labels
NAME READY STATUS RESTARTS AGE LABELS
web-load-5461 1/1 Running 0 18s tier=webQuestion 7
A pod "my-nginx-pod" (image=nginx) in custom namespace is not running. Find the problem and fix it and make it running. Note: All the supported files has been placed at root directory.
Initial Config. Understand the problem.
[root@master pv]# cat pv.yml
apiVersion: v1
kind: PersistentVolume
metadata:
name: nginx-pv-volume
labels:
type: local
namespace: production
spec:
storageClassName: manual
capacity:
storage: 10Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/mnt/data"
[root@master pv]# cat pvc.yml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: nginx-pv-claim
spec:
storageClassName: manual
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
[root@master pv]# cat pod.yml
apiVersion: v1
kind: Pod
metadata:
name: nginx
labels:
app: nginx
spec:
volumes:
- name: nginx-pv-storage
persistentVolumeClaim:
claimName: nginx-pv-claim
containers:
- name: nginx-container
image: nginx:latest
ports:
- containerPort: 80
volumeMounts:
- mountPath: /use/share/nginx/html
name: nginx-pv-storage
[root@master pv]# kubectl get all
NAME READY STATUS RESTARTS AGE
pod/nginx 0/1 Pending 0 42s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 11d
[root@master pv]# Apply the pv and pvc
[root@master pv]# cat pv.yml
apiVersion: v1
kind: PersistentVolume
metadata:
name: nginx-pv-volume
labels:
type: local
spec:
storageClassName: manual
capacity:
storage: 10Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/mnt/data"
[root@master pv]# kubectl apply -f pv.yml
persistentvolume/nginx-pv-volume created
[root@master pv]# cat pvc.yml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: nginx-pv-claim
spec:
storageClassName: manual
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
[root@master pv]# kubectl apply -f pvc.yml
persistentvolumeclaim/nginx-pv-claim created
[root@master pv]# kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS VOLUMEATTRIBUTESCLASS AGE
nginx-pv-claim Bound nginx-pv-volume 10Gi RWO manual <unset> 4s
[root@master pv]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 3m32sDescribe the pod and look for the error. Here we can see that persistentvolumeclaim "nginx-pv-claim" not found.
[root@master pv]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx 0/1 Pending 0 4s
[root@master pv]# kubectl describe pod
Name: nginx
Namespace: default
Priority: 0
Service Account: default
Node: <none>
Labels: app=nginx
Annotations: <none>
Status: Pending
IP:
IPs: <none>
Containers:
nginx-container:
Image: nginx:latest
Port: 80/TCP
Host Port: 0/TCP
Environment: <none>
Mounts:
/use/share/nginx/html from nginx-pv-storage (rw)
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-pvr2s (ro)
Conditions:
Type Status
PodScheduled False
Volumes:
nginx-pv-storage:
Type: PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
ClaimName: app-pv-claim
ReadOnly: false
kube-api-access-pvr2s:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Warning FailedScheduling 9s default-scheduler 0/3 nodes are available: persistentvolumeclaim "app-pv-claim" not found. preemption: 0/3 nodes are available: 3 Preemption is not helpful for scheduling.PVC and pod should be in the same namespace. We can see that the pvc is created in the default namespace. So we are going to modify the pvc file and deploy to production namespace, same as that of the pod namespace. We need to delete the pv as well.
[root@master pv]# kubectl get pvc -n production
No resources found in production namespace.
[root@master pv]# kubectl delete pvc nginx-pv-claim
persistentvolumeclaim "nginx-pv-claim" deleted
[root@master pv]# kubectl delete pv nginx-pv-volume
persistentvolume "nginx-pv-volume" deleted
# modify the pvc file. pv is not namespaced
[root@master pv]# cat pvc.yml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: nginx-pv-claim
namespace: production
spec:
storageClassName: manual
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
# We dont need to change the pv namespace as it is not namespaced resource
[root@master pv]# kubectl api-resources | grep persi
NAME SHORTNAMES APIVERSION NAMESPACED KIND
persistentvolumeclaims pvc v1 true PersistentVolumeClaim
persistentvolumes pv v1 false PersistentVolume
# Apply and check whether bound
[root@master pv]# kubectl apply -f pv.yml
persistentvolume/nginx-pv-volume created
[root@master pv]# kubectl apply -f pvc.yml
persistentvolumeclaim/nginx-pv-claim created
[root@master pv]# kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS VOLUMEATTRIBUTESCLASS REASON AGE
nginx-pv-volume 10Gi RWO Retain Bound production/nginx-pv-claim manual <unset> 7s
[root@master pv]# kubectl get pvc -n production
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS VOLUMEATTRIBUTESCLASS AGE
nginx-pv-claim Bound nginx-pv-volume 10Gi RWO manual <unset> 8s
# Check the pod status
[root@master pv]# kubectl get pods -n production
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 9sQuestion 8
Create a multi-container pod, "multi-pod" in development namespace using images: nginx and redis
[root@master practice-2]# kubectl run multi-pod --image=nginx --dry-run=client -o yaml > multi-pod.yml
[root@master practice-2]# vim multi-pod.yml
[root@master practice-2]# cat multi-pod.yml
apiVersion: v1
kind: Pod
metadata:
labels:
run: multi-pod
name: multi-pod
namespace: development
spec:
containers:
- image: nginx
name: nginx
- image: redis
name: redis
[root@master practice-2]# kubectl apply -f multi-pod.yml
pod/multi-pod created
[root@master practice-2]# kubectl get pods -n development
NAME READY STATUS RESTARTS AGE
multi-pod 2/2 Running 0 14sQuestion 9
A pod "nginx-pod" (image=nginx) in default namespace is not running. Find the problem and fix it to make it running. (Weightage 7%)
Describe the pod and check for the reason behind pending pod
[root@master practice-2]# cat pod.yml
apiVersion: v1
kind: Pod
metadata:
name: nginx
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
[root@master practice-2]# kubectl describe pod nginx
Name: nginx
Namespace: default
Priority: 0
Service Account: default
Node: <none>
Labels: app=nginx
Annotations: <none>
Status: Pending
IP:
IPs: <none>
Containers:
nginx:
Image: nginx
Port: <none>
Host Port: <none>
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-9774j (ro)
Conditions:
Type Status
PodScheduled False
Volumes:
kube-api-access-9774j:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Warning FailedScheduling 19s default-scheduler 0/3 nodes are available: 1 node(s) had untolerated taint {color: blue}, 1 node(s) had untolerated taint {node.kubernetes.io/not-ready: }, 1 node(s) were unschedulable. preemption: 0/3 nodes are available: 3 Preemption is not helpful for scheduling.Fix the taint and toleration node(s) had untolerated taint {color: blue}
[root@master practice-2]# vim pod.yml
[root@master practice-2]# cat pod.yml
apiVersion: v1
kind: Pod
metadata:
name: nginx
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
tolerations:
- key: "color"
operator: "Equal"
value: "blue"
effect: "NoSchedule"
[root@master practice-2]# kubectl apply -f pod.yml
pod/nginx configured
[root@master practice-2]# kubectl get pods -owide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx 1/1 Running 0 3m20s 192.168.171.135 dev-worker <none> <none>Question 10
Create a new deployment called nginx-deploy, with nginx:1.16 and 8 replica. There are 5 worker node in Cluster. Please make sure no pod will get deployed on 2 worker node (cka-cluster3-worker , cka-cluster3-worker2) (Weightage: 5%)
You dont need to perform this in exam. Creating a kind cluster with 5 nodes
[root@master kubernetes]# cat 5-wn-config.yaml
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
- role: control-plane
extraPortMappings:
- containerPort: 30003
hostPort: 30003
- role: worker
- role: worker
- role: worker
- role: worker
- role: worker
networking:
disableDefaultCNI: true
podSubnet: 192.168.0.0/16
[root@master kubernetes]# kind create cluster --image kindest/node:v1.29.14@sha256:8703bd94ee24e51b778d5556ae310c6c0fa67d761fae6379c8e0bb480e6fea29 --name cka-cluster3 --config 5-wn-config.yaml
Creating cluster "cka-cluster3" ...
✓ Ensuring node image (kindest/node:v1.29.14) 🖼
✓ Preparing nodes 📦 📦 📦 📦 📦 📦
✓ Writing configuration 📜
✓ Starting control-plane 🕹️
✓ Installing StorageClass 💾
✓ Joining worker nodes 🚜
Set kubectl context to "kind-cka-cluster3"
You can now use your cluster with:
kubectl cluster-info --context kind-cka-cluster3
Have a nice day! 👋
[root@master kubernetes]# kubectl config use-context kind-cka-cluster3
Switched to context "kind-cka-cluster3".Cordon the unwanted nodes
[root@master ~]# kubectl cordon cka-cluster3-worker
node/cka-cluster3-worker cordoned
[root@master ~]# kubectl cordon cka-cluster3-worker2
node/cka-cluster3-worker2 cordoned
[root@master practice-2]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
cka-cluster3-control-plane Ready control-plane 130m v1.29.14
cka-cluster3-worker Ready,SchedulingDisabled <none> 129m v1.29.14
cka-cluster3-worker2 Ready,SchedulingDisabled <none> 129m v1.29.14
cka-cluster3-worker3 Ready <none> 129m v1.29.14
cka-cluster3-worker4 Ready <none> 129m v1.29.14
cka-cluster3-worker5 Ready <none> 129m v1.29.14Apply the deployment and check the node of the pods deployed.
[root@master practice-2]# kubectl create deployment nginx-deploy --image=nginx:1.16 --replicas=8 --dry-run=client -o yaml > q10.yml
[root@master practice-2]# cat q10.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: nginx-deploy
name: nginx-deploy
spec:
replicas: 8
selector:
matchLabels:
app: nginx-deploy
template:
metadata:
labels:
app: nginx-deploy
spec:
containers:
- image: nginx:1.16
name: nginx
[root@master practice-2]# kubectl apply -f q10.yml
deployment.apps/nginx-deploy created
[root@master practice-2]# kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
nginx-deploy 8/8 8 8 5s
[root@master practice-2]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-deploy-68d7c886bf-2db8q 1/1 Running 0 14s 10.0.1.182 cka-cluster3-worker5 <none> <none>
nginx-deploy-68d7c886bf-6zddq 1/1 Running 0 14s 10.0.5.150 cka-cluster3-worker3 <none> <none>
nginx-deploy-68d7c886bf-8p82c 1/1 Running 0 14s 10.0.5.213 cka-cluster3-worker3 <none> <none>
nginx-deploy-68d7c886bf-h4mcc 1/1 Running 0 14s 10.0.0.12 cka-cluster3-worker4 <none> <none>
nginx-deploy-68d7c886bf-jnhf4 1/1 Running 0 14s 10.0.0.135 cka-cluster3-worker4 <none> <none>
nginx-deploy-68d7c886bf-lr64c 1/1 Running 0 14s 10.0.0.42 cka-cluster3-worker4 <none> <none>
nginx-deploy-68d7c886bf-th2gk 1/1 Running 0 14s 10.0.1.80 cka-cluster3-worker5 <none> <none>
nginx-deploy-68d7c886bf-tslnv 1/1 Running 0 14s 10.0.1.124 cka-cluster3-worker5 <none> <none>Uncordon the nodes
[root@master practice-2]# kubectl uncordon cka-cluster3-worker
node/cka-cluster3-worker uncordoned
[root@master practice-2]# kubectl uncordon cka-cluster3-worker2
node/cka-cluster3-worker2 uncordoned
[root@master practice-2]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
cka-cluster3-control-plane Ready control-plane 130m v1.29.14
cka-cluster3-worker Ready <none> 130m v1.29.14
cka-cluster3-worker2 Ready <none> 130m v1.29.14
cka-cluster3-worker3 Ready <none> 130m v1.29.14
cka-cluster3-worker4 Ready <none> 130m v1.29.14
cka-cluster3-worker5 Ready <none> 130m v1.29.14Question 11
Create a ReplicaSet (Name: web-pod, image: nginx:1.16, Replica:3) There is already a pod running in the cluster. Please make sure that the total count of pod running into a cluster is not more than 3. (Weightage 5%)
View the label of the existing pod-
[root@master practice-2]# kubectl get pods --show-labels
NAME READY STATUS RESTARTS AGE LABELS
demo-pod 1/1 Running 0 15s app=webCreate a replicaset yaml file , we dont have imperative way to create this
[root@master practice-2]# cat web-pod.yml
apiVersion: apps/v1
kind: ReplicaSet
metadata:
name: web-pod
spec:
replicas: 3
selector:
matchLabels:
app: web
template:
metadata:
labels:
app: web
spec:
containers:
- name: nginx
image: nginx:1.16
k[root@master practice-2]# kubectl apply -f web-pod.yml
replicaset.apps/web-pod created
[root@master practice-2]# kubectl get rs
NAME DESIRED CURRENT READY AGE
web-pod 3 3 2 5s
[root@master practice-2]# kubectl get pods --show-labels
NAME READY STATUS RESTARTS AGE LABELS
demo-pod 1/1 Running 0 12m app=web
web-pod-d5lvn 1/1 Running 0 44s app=web
web-pod-xknt8 1/1 Running 0 44s app=webNow two pods are created by replicaset, but the demo-pod will be as a part of the replicaset to make it 3 replicas, as it has label app=web.
Question 12
There are 3 Nodes in the cluster. Create DaemonSet ( Name:my-pod, Image:nginx ) on each node except one node dev-worker2
Taint the unwanted node dev-worker2
[root@master practice-2]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
cka-cluster3-control-plane Ready control-plane 8h v1.29.14
cka-cluster3-worker Ready <none> 8h v1.29.14
cka-cluster3-worker2 Ready <none> 8h v1.29.14
cka-cluster3-worker3 Ready <none> 8h v1.29.14
cka-cluster3-worker4 Ready <none> 8h v1.29.14
cka-cluster3-worker5 Ready <none> 8h v1.29.14
[root@master practice-2]# kubectl taint node cka-cluster3-worker env=no:NoSchedule
node/cka-cluster3-worker tainted
[root@master practice-2]# kubectl describe node cka-cluster3-worker | grep -i taint
Taints: env=no:NoSchedule[root@master practice-2]# kubectl create deployment my-pod --image=nginx --dry-run=client -o yaml > ds.yml
[root@master practice-2]# vim ds.yml
[root@master practice-2]# cat ds.yml
apiVersion: apps/v1
kind: DaemonSet
metadata:
labels:
app: my-pod
name: my-pod
spec:
selector:
matchLabels:
app: my-pod
template:
metadata:
labels:
app: my-pod
spec:
containers:
- image: nginx
name: nginx
[root@master practice-2]# kubectl apply -f ds.yml
daemonset.apps/my-pod created[root@master practice-2]# kubectl get ds -owide
NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE CONTAINERS IMAGES SELECTOR
my-pod 4 4 4 4 4 <none> 112s nginx nginx app=my-pod
[root@master practice-2]# kubectl get pods -owide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
demo-pod 1/1 Running 1 (30m ago) 6h43m 10.0.1.86 cka-cluster3-worker5 <none> <none>
my-pod-454c2 1/1 Running 0 115s 10.0.0.198 cka-cluster3-worker4 <none> <none>
my-pod-jt6h9 1/1 Running 0 115s 10.0.4.127 cka-cluster3-worker2 <none> <none>
my-pod-lgzkd 1/1 Running 0 115s 10.0.1.141 cka-cluster3-worker5 <none> <none>
my-pod-mqr4t 1/1 Running 0 115s 10.0.5.145 cka-cluster3-worker3 <none> <none>
web-pod-d5lvn 1/1 Running 1 (30m ago) 6h31m 10.0.0.18 cka-cluster3-worker4 <none> <none>
web-pod-xknt8 1/1 Running 1 (30m ago) 6h31m 10.0.3.162 cka-cluster3-worker <none> <none>Question 13
Generate a file CKA0007.txt with details about the available size of all the node in the kubernetes cluster using a custom column format as mentioned below:
| NAME | AVAILABLE_MEMORY | AVAILABLE_CPU |
|---|---|---|
| cka-cluster3-worker | ... | ... |
| cka-cluster3-worker2 | ... | ... |
| cka-cluster3-worker3 | ... | ... |
| cka-cluster3-worker4 | ... | ... |
| cka-cluster3-worker5 | ... | ... |
View the status of the nodes json
[root@master practice-2]# kubectl get nodes -o json
{
"apiVersion": "v1",
...
"items": [
{
"metadata": {
"name": "cka-cluster3-worker5",
},
"status": {
"allocatable": {
"cpu": "6",
...
"memory": "4179948Ki",
}
}
}
]
...
}[root@master practice-2]# kubectl get node -o custom-columns=NAME:.metadata.name,AVAILABLE_MEMORY:.status.allocatable.memory,AVAILABLE_CPU:.status.allocatable.cpu
NAME AVAILABLE_MEMORY AVAILABLE_CPU
cka-cluster3-control-plane 4179948Ki 6
cka-cluster3-worker 4179948Ki 6
cka-cluster3-worker2 4179948Ki 6
cka-cluster3-worker3 4179948Ki 6
cka-cluster3-worker4 4179948Ki 6
cka-cluster3-worker5 4179948Ki 6Write in the file
[root@master practice-2]# kubectl get node -o custom-columns=NAME:.metadata.name,AVAILABLE_MEMORY:.status.allocatable.memory,AVAILABLE_CPU:.status.allocatable.cpu > cka0007.txt
[root@master practice-2]# cat cka0007.txt
NAME AVAILABLE_MEMORY AVAILABLE_CPU
cka-cluster3-control-plane 4179948Ki 6
cka-cluster3-worker 4179948Ki 6
cka-cluster3-worker2 4179948Ki 6
cka-cluster3-worker3 4179948Ki 6
cka-cluster3-worker4 4179948Ki 6
cka-cluster3-worker5 4179948Ki 6Question 14
There are various pods running in all the namespaces of kubernetes cluster. Write a command to "/opt/pods_asc.sh" which list all the pods sorted by their AGE in ascending order.
Get all the pods using -A ,and sort it using timestamp
[root@master practice-2]# kubectl get pods -A --sort-by=.metadata.creationTimestamp
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system kube-controller-manager-cka-cluster3-control-plane 1/1 Running 18 (23m ago) 13h
kube-system kube-scheduler-cka-cluster3-control-plane 1/1 Running 18 (23m ago) 13h
local-path-storage local-path-provisioner-55ff44bb8-b4pqp 1/1 Running 3 (4h45m ago) 13h
kube-system kube-proxy-rc767 1/1 Running 5 (4h45m ago) 13h
kube-system coredns-76f75df574-qrmb7 1/1 Running 4 (4h45m ago) 13h
kube-system coredns-76f75df574-tz7bh 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-2x68g 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-mtv59 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-gnbgw 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-ffljb 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-fdn98 1/1 Running 4 (4h45m ago) 13h
kube-system cilium-qvfzj 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-wvrhx 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-t8vtg 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-2l9wk 1/1 Running 5 (4h45m ago) 12h
kube-system cilium-operator-db96c7c9c-n9cwx 1/1 Running 12 (23m ago) 12h
kube-system cilium-operator-db96c7c9c-6mmvz 1/1 Running 10 (55m ago) 12h
kube-system cilium-dpvdk 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-4d6mt 1/1 Running 4 (4h45m ago) 12h
kube-system kube-apiserver-cka-cluster3-control-plane 1/1 Running 0 4h45m
kube-system etcd-cka-cluster3-control-plane 1/1 Running 0 4h45mConvert the output into ascending order by adding tac
[root@master practice-2]# kubectl get pods -A --sort-by=.metadata.creationTimestamp | tac
kube-system etcd-cka-cluster3-control-plane 1/1 Running 0 4h45m
kube-system kube-apiserver-cka-cluster3-control-plane 1/1 Running 0 4h45m
kube-system cilium-4d6mt 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-dpvdk 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-operator-db96c7c9c-6mmvz 1/1 Running 10 (55m ago) 12h
kube-system cilium-operator-db96c7c9c-n9cwx 1/1 Running 12 (23m ago) 12h
kube-system cilium-2l9wk 1/1 Running 5 (4h45m ago) 12h
kube-system cilium-t8vtg 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-wvrhx 1/1 Running 4 (4h45m ago) 12h
kube-system cilium-qvfzj 1/1 Running 4 (4h45m ago) 12h
kube-system kube-proxy-fdn98 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-ffljb 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-gnbgw 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-mtv59 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-2x68g 1/1 Running 4 (4h45m ago) 13h
kube-system coredns-76f75df574-tz7bh 1/1 Running 4 (4h45m ago) 13h
kube-system coredns-76f75df574-qrmb7 1/1 Running 4 (4h45m ago) 13h
kube-system kube-proxy-rc767 1/1 Running 5 (4h45m ago) 13h
local-path-storage local-path-provisioner-55ff44bb8-b4pqp 1/1 Running 3 (4h45m ago) 13h
kube-system kube-scheduler-cka-cluster3-control-plane 1/1 Running 18 (23m ago) 13h
kube-system kube-controller-manager-cka-cluster3-control-plane 1/1 Running 18 (23m ago) 13h
NAMESPACE NAME READY STATUS RESTARTS AGEWrite the command in shell and provide access to execute
[root@master practice-2]# echo "kubectl get pods -A --sort-by=.metadata.creationTimestamp | tac" > /opt/pods_asc.sh
[root@master practice-2]# cat /opt/pods_asc.sh
kubectl get pods -A --sort-by=.metadata.creationTimestamp | tac
[root@master practice-2]# chmod +x /opt/pods_asc.sh Question 15
Create a deployment called web-proj-268, with image nginx:1.16 and 1 replica. Next upgrade the deployment version to 1.17 using rolling update. Make sure that the version upgrade is recorded in the resource annotation.
Create a deployment with nginx version 1.16
[root@master practice-2]# kubectl create deployment web-proj-268 --image=nginx:1.16 --replicas=1 --dry-run=client -o yaml > web-proj-268.yml
[root@master practice-2]# vim web-proj-268.yml
[root@master practice-2]# cat web-proj-268.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: web-proj-268
name: web-proj-268
spec:
replicas: 1
selector:
matchLabels:
app: web-proj-268
template:
metadata:
labels:
app: web-proj-268
spec:
containers:
- image: nginx:1.16
name: nginx
[root@master practice-2]# kubectl get pods
NAME READY STATUS RESTARTS AGE
web-proj-268-68b8987b5d-57mql 1/1 Running 0 56s
[root@master practice-2]# kubectl describe pod web-proj-268-68b8987b5d-57mql | grep -i image:
Image: nginx:1.16Configure the pod to nginx version 1.17 and apply the changes with --record
[root@master practice-2]# cat web-proj-268.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: web-proj-268
name: web-proj-268
spec:
replicas: 1
selector:
matchLabels:
app: web-proj-268
template:
metadata:
labels:
app: web-proj-268
spec:
containers:
- image: nginx:1.17
name: nginx
[root@master practice-2]# kubectl apply -f web-proj-268.yml --record
Flag --record has been deprecated, --record will be removed in the future
deployment.apps/web-proj-268 configured
[root@master practice-2]# kubectl get pods
NAME READY STATUS RESTARTS AGE
web-proj-268-5564fbcd55-g85mf 1/1 Running 0 118s
[root@master practice-2]# kubectl describe pod web-proj-268-5564fbcd55-g85mf | grep -i image:
Image: nginx:1.17View the rollout record
[root@master practice-2]# kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
web-proj-268 1/1 1 1 6m4s
[root@master practice-2]# kubectl rollout history deployment web-proj-268
deployment.apps/web-proj-268
REVISION CHANGE-CAUSE
1 <none>
2 kubectl apply --filename=web-proj-268.yml --record=trueQuestion 16
Create a pod nginx-k8s using image nginx and initContainer "git-k8s" with image alpine/git. Volume mount path of the main container "/usr/share/nginx/html". Nginx index.html should be override with shared volume. index.html file cloned from path "https://github.com/jhawithu/k8s-nginx"
[root@master ~]# kubectl run pod nginx-k8s --image=nginx --dry-run=client -o yaml > nginx-k8s.yml
[root@master ~]# cat nginx-k8s.yml
apiVersion: v1
kind: Pod
metadata:
labels:
run: pod
name: nginx-k8s
spec:
containers:
- image: nginx
name: nginx-k8s
ports:
- containerPort: 80
volumeMounts:
- mountPath: "/usr/share/nginx/html"
name: my-data
initContainers:
- name: git-k8s
image: alpine/git
command: ['git','clone','https://github.com/jhawithu/k8s-nginx','/data']
volumeMounts:
- mountPath: "/data"
name: my-data
volumes:
- name: my-data
emptyDir: {}
[root@master ~]# kubectl apply -f nginx-k8s.yml
pod/nginx-k8s created
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-k8s 0/1 PodInitializing 0 8s
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-k8s 1/1 Running 0 13s[root@master ~]# kubectl exec -it nginx-k8s -- bash
Defaulted container "nginx-k8s" out of: nginx-k8s, git-k8s (init)
root@nginx-k8s:/# cd /usr/share/nginx/html/
root@nginx-k8s:/usr/share/nginx/html# ls
README.md index.html
root@nginx-k8s:/usr/share/nginx/html# cat index.html
<html>
<head>
<title>I Love Kubernetes</title>
<meta charset="utf-8" />
</head>
<body>
<h1>
Hello world !!!
</h1>
</body>
</html>Question 17
Create a deployment with the below information mentioned in the table using the provided file "deployment.yml" at location "/root". There are some typo in the file, that need to fix accordingly and create the deployment successfully in default namespace.
| Deployment Name | nginx-deployment |
|---|---|
| Image | nginx:latest |
| ContainerPort | 80 |
| Replicas | 3 |
Creat using --dry-run=client mentioning the image, name, replicas, and port then check with the existing file and correct if there is any errors in the yml file. |
[root@master ~]# kubectl create deployment nginx-deploy --image=nginx:latest --replicas=3 --port=80 --dry-run=client -o yaml > deployment.yml
[root@master ~]#
[root@master ~]# vim deployment.yml
[root@master ~]# cat deployment.yml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: nginx-deploy
name: nginx-deploy
spec:
replicas: 3
selector:
matchLabels:
app: nginx-deploy
template:
metadata:
labels:
app: nginx-deploy
spec:
containers:
- image: nginx:latest
name: nginx
ports:
- containerPort: 80
[root@master ~]# kubectl apply -f deployment.yml
deployment.apps/nginx-deploy created
[root@master ~]# kubectl get deployment
NAME READY UP-TO-DATE AVAILABLE AGE
nginx-deploy 3/3 3 3 11s
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-deploy-864c7757b9-8mw4p 1/1 Running 0 15s
nginx-deploy-864c7757b9-fjhjp 1/1 Running 0 15s
nginx-deploy-864c7757b9-lnlfs 1/1 Running 0 15s