komenda kubernetes kubectl
# Get commands with basic output
kubectl get services # List all services in the namespace
kubectl get pods --all-namespaces # List all pods in all namespaces
kubectl get pods -o wide # List all pods in the current namespace, with more details
kubectl get deployment my-dep # List a particular deployment
kubectl get pods # List all pods in the namespace
kubectl get pod my-pod -o yaml # Get a pod's YAML
# Describe commands with verbose output
kubectl describe nodes my-node
kubectl describe pods my-pod
# List Services Sorted by Name
kubectl get services --sort-by=.metadata.name
# List pods Sorted by Restart Count
kubectl get pods --sort-by='.status.containerStatuses[0].restartCount'
# List PersistentVolumes sorted by capacity
kubectl get pv --sort-by=.spec.capacity.storage
# Get the version label of all pods with label app=cassandra
kubectl get pods --selector=app=cassandra -o \
jsonpath='{.items[*].metadata.labels.version}'
# Retrieve the value of a key with dots, e.g. 'ca.crt'
kubectl get configmap myconfig \
-o jsonpath='{.data.ca\.crt}'
# Get all worker nodes (use a selector to exclude results that have a label
# named 'node-role.kubernetes.io/master')
kubectl get node --selector='!node-role.kubernetes.io/master'
# Get all running pods in the namespace
kubectl get pods --field-selector=status.phase=Running
# Get ExternalIPs of all nodes
kubectl get nodes -o jsonpath='{.items[*].status.addresses[?(@.type=="ExternalIP")].address}'
# List Names of Pods that belong to Particular RC
# "jq" command useful for transformations that are too complex for jsonpath, it can be found at https://stedolan.github.io/jq/
sel=${$(kubectl get rc my-rc --output=json | jq -j '.spec.selector | to_entries | .[] | "\(.key)=\(.value),"')%?}
echo $(kubectl get pods --selector=$sel --output=jsonpath={.items..metadata.name})
# Show labels for all pods (or any other Kubernetes object that supports labelling)
kubectl get pods --show-labels
# Check which nodes are ready
JSONPATH='{range .items[*]}{@.metadata.name}:{range @.status.conditions[*]}{@.type}={@.status};{end}{end}' \
&& kubectl get nodes -o jsonpath="$JSONPATH" | grep "Ready=True"
# Output decoded secrets without external tools
kubectl get secret my-secret -o go-template='{{range $k,$v := .data}}{{"### "}}{{$k}}{{"\n"}}{{$v|base64decode}}{{"\n\n"}}{{end}}'
# List all Secrets currently in use by a pod
kubectl get pods -o json | jq '.items[].spec.containers[].env[]?.valueFrom.secretKeyRef.name' | grep -v null | sort | uniq
# List all containerIDs of initContainer of all pods
# Helpful when cleaning up stopped containers, while avoiding removal of initContainers.
kubectl get pods --all-namespaces -o jsonpath='{range .items[*].status.initContainerStatuses[*]}{.containerID}{"\n"}{end}' | cut -d/ -f3
# List Events sorted by timestamp
kubectl get events --sort-by=.metadata.creationTimestamp
# Compares the current state of the cluster against the state that the cluster would be in if the manifest was applied.
kubectl diff -f ./my-manifest.yaml
# Produce a period-delimited tree of all keys returned for nodes
# Helpful when locating a key within a complex nested JSON structure
kubectl get nodes -o json | jq -c 'paths|join(".")'
# Produce a period-delimited tree of all keys returned for pods, etc
kubectl get pods -o json | jq -c 'paths|join(".")'
# Produce ENV for all pods, assuming you have a default container for the pods, default namespace and the `env` command is supported.
# Helpful when running any supported command across all pods, not just `env`
for pod in $(kubectl get po --output=jsonpath={.items..metadata.name}); do echo $pod && kubectl exec -it $pod -- env; done
suraj meshram
