Kubectl Cheatsheet
Kubernetes Namespaces Management
Efficiently manage your Kubernetes resources by understanding and utilizing namespaces. This section covers commands to view all namespaces and filter resources within specific ones.
Show all namespaces.
kubectl --all-namespaces
Shorthand for viewing all namespaces:
kubectl -A
Kubernetes Pod Logging
Accessing and analyzing pod logs is crucial for debugging and monitoring your Kubernetes applications. Learn how to retrieve logs from specific pods and namespaces.
kubectl --namespace my-namespace get pods
Get logs for a specific pod:
kubectl logs pod-name
Get logs for a pod in a specific namespace, with time constraints and timestamps:
kubectl logs <pod_name> -n <namespace> --since=12h --timestamps
Tail logs in real-time
Stream logs as they are generated:
kubectl logs -f
Retrieve previous logs
Access logs from a previous instance of a pod:
kubectl logs -p
Limit log output
View only the last N lines of logs:
--tail=20
Inspecting Kubernetes ConfigMaps
ConfigMaps are essential for decoupling configuration from application code. This section demonstrates how to view and inspect ConfigMap details using kubectl.
First, confirm the name of the ConfigMap you want to inspect. Here's how to list ConfigMaps in a specific namespace:
kubectl get configmap -n bridge
Example output:
NAME DATA AGE
bridge-conf-configmap 1 144d
bridge-init-conf-configmap 1 567d
bridge-jks-configmap 1 144d
kube-root-ca.crt 1 385d
Now, describe the settings of a specific ConfigMap, filtering for relevant information:
kubectl describe configmaps bridge-conf-configmap -n bridge | grep -C 3 maxQueuedRequests
Example output snippet:
idleThreadTimeout: 60s
maxThreads: 2048
minThreads: 1024
maxQueuedRequests: 4096
requestLog:
appenders:
- type: console
Kubernetes Resources and Documentation
For further exploration and deeper understanding of Kubernetes and kubectl commands, refer to the following resources: