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Computer Notes/Kubernetes/Kubernetes Command-Line Cheat Sheet

Mflavell — Thu, 10 Sep 2026 00:14:12 GMT

Created page with "'''Kubernetes Command-Line Cheat Sheet''' is a reference guide for standard operations using the <code>kubectl</code> command-line interface to manage Kubernetes clusters, workloads, and node infrastructure. == Cluster Context & Namespaces == {| class="wikitable" ! Command !! Description |- | <code>kubectl config get-contexts</code> || List all available cluster contexts. |- | <code>kubectl config use-context <context-name></code> || Switch active cluster context...."

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'''Kubernetes Command-Line Cheat Sheet''' is a reference guide for standard operations using the <code>kubectl</code> command-line interface to manage Kubernetes clusters, workloads, and node infrastructure.

== Cluster Context & Namespaces ==
{| class="wikitable"
! Command !! Description
|-
| <code>kubectl config get-contexts</code> || List all available cluster contexts.
|-
| <code>kubectl config use-context <context-name></code> || Switch active cluster context.
|-
| <code>kubectl config set-context --current --namespace=<ns></code> || Set default namespace for current context.
|-
| <code>kubectl get ns</code> || List all namespaces in the cluster.
|}

== Viewing & Inspecting Resources ==
{| class="wikitable"
! Command !! Description
|-
| <code>kubectl get pods -A</code> || List all pods across all namespaces.
|-
| <code>kubectl get pods -o wide</code> || List pods with IP addresses and node assignments.
|-
| <code>kubectl get all -n <namespace></code> || Show all active resources in a specific namespace.
|-
| <code>kubectl describe <resource>/<name></code> || View detailed state, events, and configuration.
|-
| <code>kubectl get <resource> <name> -o yaml</code> || Export resource manifest to YAML format.
|}

== Deploying & Managing Workloads ==
{| class="wikitable"
! Command !! Description
|-
| <code>kubectl apply -f <file.yaml></code> || Create or update resources declaratively.
|-
| <code>kubectl delete -f <file.yaml></code> || Delete resources defined in a YAML manifest.
|-
| <code>kubectl scale deploy/<name> --replicas=<N></code> || Scale the replica count of a Deployment.
|-
| <code>kubectl rollout restart deploy/<name></code> || Perform a zero-downtime rolling restart.
|-
| <code>kubectl rollout undo deploy/<name></code> || Roll back to the previous deployment revision.
|}

== Debugging & Observability ==
{| class="wikitable"
! Command !! Description
|-
| <code>kubectl logs -f <pod-name></code> || Stream real-time logs from a pod container.
|-
| <code>kubectl logs -p <pod-name></code> || View logs from a previous crashed container instance.
|-
| <code>kubectl exec -it <pod-name> -- /bin/sh</code> || Open an interactive shell inside a running pod.
|-
| <code>kubectl port-forward svc/<name> 8080:80</code> || Forward local port 8080 to cluster service port 80.
|-
| <code>kubectl get events --sort-by='.metadata.creationTimestamp'</code> || List recent cluster events sorted by timestamp.
|-
| <code>kubectl top pods</code> / <code>kubectl top nodes</code> || Display live CPU and memory metrics.
|}

== Node Operations & Maintenance ==
{| class="wikitable"
! Command !! Description
|-
| <code>kubectl get nodes</code> || List all cluster nodes and their current status.
|-
| <code>kubectl cordon <node-name></code> || Mark a node as unschedulable.
|-
| <code>kubectl drain <node-name> --ignore-daemonsets</code> || Safely evict all pods before node maintenance.
|-
| <code>kubectl uncordon <node-name></code> || Mark a node as schedulable again.
|}

== Essential Productivity Shell Shortcuts ==
Add these shortcuts to your shell profile (<code>~/.bashrc</code> or <code>~/.zshrc</code>) to speed up workflow:

<syntaxhighlight lang="bash">
alias k='kubectl'
alias kgp='kubectl get pods'
alias kgs='kubectl get svc'
alias kgd='kubectl get deployments'
alias kdp='kubectl describe pod'
alias kl='kubectl logs -f'
</syntaxhighlight>

== See Also ==
* [[Kubernetes]]
* [[Secure Shell]]

[[Category:Kubernetes]]
[[Category:Cheat Sheets]]
[[Category:System Administration]]

Computer Notes/Kubernetes

Mflavell — Thu, 10 Sep 2026 00:13:56 GMT

← Older revision		Revision as of 00:13, 10 September 2026
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	[[Computer Notes/Kubernetes\|Kubernetes Command-Line Cheat Sheet]]		[[Computer Notes/Kubernetes/Kubernetes Command-Line Cheat Sheet\|Kubernetes Command-Line Cheat Sheet]]

Computer Notes/Kubernetes

Mflavell — Thu, 10 Sep 2026 00:13:25 GMT

Created page with "Kubernetes Command-Line Cheat Sheet"

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[[Computer Notes/Kubernetes|Kubernetes Command-Line Cheat Sheet]]

Computer Notes

Mflavell — Thu, 10 Sep 2026 00:12:52 GMT

← Older revision		Revision as of 00:12, 10 September 2026
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	[[Computer Notes/Security Services Platform\|Security Services Platform]]		[[Computer Notes/Security Services Platform\|Security Services Platform]]

			[[Computer Notes/Kubernetes\|Kubernetes]]

			[[Computer Notes/CA Siteminder\|CA Siteminder]]

	[[Computer Notes/CA Siteminder\|CA Siteminder]]		[[Computer Notes/CA Siteminder\|CA Siteminder]]

Computer Notes/Security Services Platform/Accessing the K8 Cluster

Mflavell — Thu, 10 Sep 2026 00:05:38 GMT

Step 1: Generate an SSH Key Pair on SSPI

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Computer Notes/Security Services Platform/Accessing the K8 Cluster

Mflavell — Thu, 10 Sep 2026 00:02:35 GMT

Created page with "'''SSH key pair authentication''' is a public-key cryptographic mechanism used within the Secure Shell (SSH) protocol to authenticate users or machines attempting to establish a remote network connection. Unlike traditional password-based authentication, key pair authentication relies on asymmetric cryptography, utilizing a mathematically linked pair of cryptographic keys: a '''public key''' and a '''private key'''. == Mechanism and Architecture == SSH key authenticatio..."

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'''SSH key pair authentication''' is a public-key cryptographic mechanism used within the Secure Shell (SSH) protocol to authenticate users or machines attempting to establish a remote network connection. Unlike traditional password-based authentication, key pair authentication relies on asymmetric cryptography, utilizing a mathematically linked pair of cryptographic keys: a '''public key''' and a '''private key'''.

== Mechanism and Architecture ==
SSH key authentication operates on a challenge-response model designed to verify identity without ever transmitting sensitive credential data over the network.

* '''Private Key:''' Kept strictly confidential on the client machine. It is protected by local file permissions (typically <code>chmod 600</code>) and can be further secured using a passphrase.
* '''Public Key:''' Placed on the target server, where it is stored in the remote user's configuration file (commonly <code>~/.ssh/authorized_keys</code>).

When a client requests an SSH session:
# The client sends a signal to the server identifying the public key it wishes to use for authentication.
# The server checks its <code>authorized_keys</code> file to confirm the key is authorized for the requested account.
# The server generates a cryptographic challenge (a random string of data) and sends it to the client.
# The client uses its local private key to sign the challenge, generating a digital signature, which is sent back to the server.
# The server uses the stored public key to verify the signature. If valid, the session is established.

== Common Algorithms and Key Generation ==
Key pairs are generated using software utilities such as OpenSSH's <code>ssh-keygen</code>. The security and performance of the key pair depend on the underlying mathematical algorithm:

* '''Ed25519:''' An Elliptic Curve Digital Signature Algorithm (EdDSA) scheme offering high performance, immunity to side-channel attacks, and a fixed key length of 256 bits. It is widely considered the modern standard.
* '''ECDSA:''' An elliptic curve implementation based on NIST curves. While secure, implementation flaws in random number generation can compromise private keys.
* '''RSA:''' A historical standard based on the integer factorization problem. Modern security guidelines mandate key lengths of 3072 or 4096 bits, as shorter lengths (e.g., 2048-bit) are increasingly vulnerable to advancing computational power.

== Advantages and Applications ==
SSH key pair authentication offers significant operational benefits over standard passwords:

* '''Mitigation of Brute-Force Attacks:''' Modern SSH keys possess high entropy, rendering dictionary and online brute-force attacks mathematically infeasible.
* '''Non-Interactive Automation:''' Keys facilitate secure, automated execution of administrative scripts, deployment pipelines (CI/CD), and infrastructure management tools without human intervention.
* '''Granular Access Control:''' System administrators can grant or revoke specific user access instantly by adding or removing individual public keys from a server, eliminating the need to reset global account passwords.

== See Also ==
* [[Secure Shell]]
* [[Public-key cryptography]]
* [[ssh-keygen]]

[[Category:Computer access control]]
[[Category:Network security]]

Computer Notes/Security Services Platform

Mflavell — Thu, 10 Sep 2026 00:02:20 GMT

← Older revision		Revision as of 00:02, 10 September 2026
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	[[Computer Notes]] > Security Services Platform		[[Computer Notes]] > Security Services Platform

			[[Computer Notes/Security Services Platform/Accessing the K8 Cluster\|Accessing the K8 Cluster]]

	= Overview =		= Overview =

← Older revision		Revision as of 00:12, 10 September 2026
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	[[Computer Notes/Security Services Platform\|Security Services Platform]]		[[Computer Notes/Security Services Platform\|Security Services Platform]]

			[[Computer Notes/Kubernetes\|Kubernetes]]

			[[Computer Notes/CA Siteminder\|CA Siteminder]]

	[[Computer Notes/CA Siteminder\|CA Siteminder]]		[[Computer Notes/CA Siteminder\|CA Siteminder]]