Linux Foundation CKA Quiz 6 Topic 7 Questions 26-30

Question: 1

Get the number of schedulable nodes and write to a file

/opt/schedulable-nodes.txt

Akubectl get nodes -o jsonpath='{range
.items[*]}{.metadata.name}
{.spec.taints[?(@.effect=='NoSchedule')].effect}{\'\n\'}{end}'
| awk 'NF==1 {print $0}' > /opt/schedulable-nodes.txt
// Verify
cat /opt/schedulable-nodes.txt

Bkubectl get nodes -o jsonpath='{range
.items[*]}{.metadata.name}
{.spec.taints[?(@.effect=='NoSchedule')].effect}{\'\n\'}{end}'
| awk 'NF==11 {print $0}' > /opt/schedulable-nodes.txt
// Verify
cat /opt/schedulable-nodes.txt

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Question: 2

Fix a node that shows as non-ready

AKubectl get nodes
// Check which node shows a not ready
kubectl describe nodes ''node-name''
// Login to the node which shows as not ready and check the
process for kubelet, docker , kube-proxy.
// systemctl status kubelet (or) ps -aux | grep -i ''processname''
// If the process is not started, then start using
systemctl start kubelet / docker
// Verify
ps -auxxww | grep -i ''process-name''
kubectl get nodes

BKubectl get nodes
// Check which node shows a not ready
kubectl describe nodes ''node-name''
// Login to the node which shows as not ready and check the
systemctl start kubelet / docker
// Verify
ps -auxxww | grep -i ''process-name''
kubectl get nodes

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Question: 3

Deploy a pod with image=redis on a node with label disktype=ssd

A// Get list of nodes
kubectl get nodes
//Get node with the label disktype=ssd
kubectl get no -l disktype=ssd
// Create a sample yaml file
kubectl run node-redis --generator=run-pod/v1 --image=redis --dry
run -o yaml > test-redis.yaml
// Edit test-redis.yaml file and add nodeSelector
vim test-redis.yaml
apiVersion: v1
kind: Pod
metadata:
name: redis
spec:
nodeSelector:
disktype: ssd
containers:
- name: node-redis
image: redis
imagePullPolicy: IfNotPresent
kubectl apply -f test-redis.yaml
/ // Verify
K kubectl get po -o wide

B// Get list of nodes
kubectl get nodes
//Get node with the label disktype=ssd
kubectl get no -l disktype=ssd
// Create a sample yaml file
kubectl run node-redis --generator=run-pod/v1 --image=redis --dry
run -o yaml > test-redis.yaml
// Edit test-redis.yaml file and add nodeSelector
vim test-redis.yaml
apiVersion: v1
- name: node-redis
image: redis
imagePullPolicy: IfNotPresent
kubectl apply -f test-redis.yaml
/ // Verify
K kubectl get po -o wide

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Question: 4

Add a taint to node "worker-2" with effect as "NoSchedule" and

list the node with taint effect as "NoSchedule"

A// Add taint to node 'worker-2'
kubectl taint nodes worker-2 key=value:NoSchedule
.items[*]}{.metadata.name} {.spec.taints[?(
@.effect=='NoSchedule' )].effect}{\'\n\'}{end}' | awk 'NF==2
{print $0}'

B// Add taint to node 'worker-2'
kubectl taint nodes worker-2 key=value:NoSchedule
// Verify
// Using ''custom-coloumns'' , you can customize which coloumn to
be printed
kubectl get nodes -o customcolumns=NAME:.metadata.name,TAINTS:.spec.taints --no-headers
// Using jsonpath
kubectl get nodes -o jsonpath='{range
.items[*]}{.metadata.name} {.spec.taints[?(
@.effect=='NoSchedule' )].effect}{\'\n\'}{end}' | awk 'NF==2
{print $0}'

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Question: 5

SIMULATION

Check to see how many worker nodes are ready (not including nodes tainted NoSchedule) and write the number to /opt/KUCC00104/kucc00104.txt.

Asolution

Bsolution

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Linux Foundation CKA Quiz:6 Topic:7 Questions:26-30