Kubernetes - Cheat Sheet

1kubectl config get-clusters

1kubectl cluster-info
2Kubernetes master is running at https://172.17.0.58:8443

1kubectl config get-contexts

1kubectl config current-context

1kubectl config use-context docker-desktop

1kubectl config set-context $(kubectl config current-context) --namespace=my-namespace

1kubectl get all
2kubectl get namespaces
3kubectl get configmaps
4kubectl get nodes
5kubectl get pods
6kubectl get rs
7kubectl get svc kuard
8kubectl get endpoints kuard

1kubectl config set-context $(kubectl config current-context) --namespace=my-namespace

1kubectl get pods --show-labels

1kubectl get pods -l environment=production,tier!=frontend
2kubectl get pods -l 'environment in (production,test),tier notin (frontend,backend)'

1kubectl describe nodes [id]
2kubectl describe pods [id]
3kubectl describe rs [id]
4kubectl describe svc kuard [id]
5kubectl describe endpoints kuard [id]

1kubectl delete nodes [id]
2kubectl delete pods [id]
3kubectl delete rs [id]
4kubectl delete svc kuard [id]
5kubectl delete endpoints kuard [id]

1kubectl delete pod-name --grace-period=0 --force

1kubectl run kuard --generator=run-pod/v1 --image=gcr.io/kuar-demo/kuard-amd64:1 --output yaml --export --dry-run > kuard-pod.yml
2kubectl apply -f kuard-pod.yml

1kubectl run kuard --image=gcr.io/kuar-demo/kuard-amd64:1 --output yaml --export --dry-run > kuard-deployment.yml
2kubectl apply -f kuard-deployment.yml

1kubectl expose deployment kuard --port 8080 --target-port=8080 --output yaml --export --dry-run > kuard-service.yml
2kubectl apply -f kuard-service.yml

1kubectl run my-cool-app —-image=me/my-cool-app:v1 --output yaml --export --dry-run > my-cool-app.yaml

1kubectl get deployment my-cool-app --output yaml --export > my-cool-app.yaml

 1kubectl logs -l app=kuard
 2
 3# Get logs for previously terminated container.
 4kubectl logs POD_NAME --previous
 5
 6# Watch logs in real time.
 7kubectl attach POD_NAME
 8
 9# Copy log files out of pod (Requires `tar` binary in container).
10kubectl cp POD_NAME:/var/log .

1kubectl port-forward deployment/kuard 8080:8080

1kubectl scale deployment nginx-deployment --replicas=10

1kubectl autoscale deployment nginx-deployment --min=10 --max=15 --cpu-percent=80

 1# Get rollout status.
 2kubectl rollout status deployment/nginx-deployment
 3
 4# Get rollout history.
 5
 6kubectl rollout history deployment/nginx-deployment
 7kubectl rollout history deployment/nginx-deployment --revision=2
 8
 9# Undo a rollout.
10
11kubectl rollout undo deployment/nginx-deployment
12kubectl rollout undo deployment/nginx-deployment --to-revision=2
13
14# Pause/resume a rollout
15
16kubectl rollout pause deployment/nginx-deployment
17kubectl rollout resume deploy/nginx-deployment

 1# Get commands with basic output
 2kubectl get services                          # List all services in the namespace
 3kubectl get pods --all-namespaces             # List all pods in all namespaces
 4kubectl get pods -o wide                      # List all pods in the namespace, with more details
 5kubectl get deployment my-dep                 # List a particular deployment
 6kubectl get pods --include-uninitialized      # List all pods in the namespace, including uninitialized ones
 7
 8# Describe commands with verbose output
 9kubectl describe nodes my-node
10kubectl describe pods my-pod
11
12kubectl get services --sort-by=.metadata.name # List Services Sorted by Name
13
14# List pods Sorted by Restart Count
15kubectl get pods --sort-by='.status.containerStatuses[0].restartCount'
16
17# Get the version label of all pods with label app=cassandra
18kubectl get pods --selector=app=cassandra rc -o \
19  jsonpath='{.items[*].metadata.labels.version}'
20
21# Get all worker nodes (use a selector to exclude results that have a label
22# named 'node-role.kubernetes.io/master')
23kubectl get node --selector='!node-role.kubernetes.io/master'
24
25# Get all running pods in the namespace
26kubectl get pods --field-selector=status.phase=Running
27
28# Get ExternalIPs of all nodes
29kubectl get nodes -o jsonpath='{.items[*].status.addresses[?(@.type=="ExternalIP")].address}'
30
31# List Names of Pods that belong to Particular RC
32# "jq" command useful for transformations that are too complex for jsonpath, it can be found at https://stedolan.github.io/jq/
33sel=${$(kubectl get rc my-rc --output=json | jq -j '.spec.selector | to_entries | .[] | "\(.key)=\(.value),"')%?}
34echo $(kubectl get pods --selector=$sel --output=jsonpath={.items..metadata.name})
35
36# Show labels for all pods (or any other Kubernetes object that supports labelling)
37# Also uses "jq"
38for item in $( kubectl get pod --output=name); do printf "Labels for %s\n" "$item" | grep --color -E '[^/]+$' && kubectl get "$item" --output=json | jq -r -S '.metadata.labels | to_entries | .[] | " \(.key)=\(.value)"' 2>/dev/null; printf "\n"; done
39
40# Check which nodes are ready
41JSONPATH='{range .items[*]}{@.metadata.name}:{range @.status.conditions[*]}{@.type}={@.status};{end}{end}' \
42 && kubectl get nodes -o jsonpath="$JSONPATH" | grep "Ready=True"
43
44# List all Secrets currently in use by a pod
45kubectl get pods -o json | jq '.items[].spec.containers[].env[]?.valueFrom.secretKeyRef.name' | grep -v null | sort | uniq
46
47# List Events sorted by timestamp
48kubectl get events --sort-by=.metadata.creationTimestamp