luckylittle

Mock Exam

1

Q1. The metric node_cpu_temp_celcius reports the current temperature of a nodes CPU in celsius. What query will return the average temperature across all CPUs on a per node basis? The query should return {instance=“node1”} 23.5 //average temp across all CPUs on node1 {instance=“node2”} 33.5 //average temp across all CPUs on node2.

node_cpu_temp_celsius{instance="node1", cpu="0"} 28
node_cpu_temp_celsius{instance="node1", cpu="1"} 19
node_cpu_temp_celsius{instance="node2", cpu="0"} 36
node_cpu_temp_celsius{instance="node2", cpu="1"} 31

axeal

#!/bin/bash

export PATH=./:$PATH

# Determine OS and architecture
case $(uname -s) in
	Linux*)     os="linux" ;;
	Darwin*)    os="darwin" ;;
	*)          echo "Unsupported OS detected"; exit;;
esac

dkeightley

Install the ALB controller

I installed it via helm without IAM roles for Service Accounts (IRSA) configured for the EKS cluster, so the controller pods used the policy's attached to the underlying instance profile of the worker nodes.

• https://kubernetes-sigs.github.io/aws-load-balancer-controller/v2.3/deploy/installation/#summary

Install Rancher

To deploy Rancher, I used the following helm install command, note using a values file can make this syntax clearer and easier.

n1snt

Oh my zsh.

Install ZSH.

sudo apt install zsh-autosuggestions zsh-syntax-highlighting zsh

Install Oh my ZSH.

ksingh7

Get Token for API Authentication

oc whoami -t

Get Prometheus Route URL

oc get route -n openshift-monitoring | grep -i prometheus

Run sample curl request

tuxfight3r

use kubectl to patch configmap via json patch operations (add/remove/replace/test)

## Add a new key to the existing configmap
$ kubectl patch cm demo-app-config --type json --patch '[{ "op": "add", "path": "/data/TEST_VALUE", "value": "test_key" }]'
configmap/demo-app-config patched

$ kubectl get cm demo-app-config -o json | jq .data.TEST_VALUE
"test_key"

superseb

RKE2 commands

• Updated on May 29 to accommodate etcd container not having /bin/sh available anymore.

Install

curl -sL https://get.rke2.io | sh
systemctl daemon-reload
systemctl start rke2-server

smijar

ref

https://rancher.com/docs/k3s/latest/en/installation/kube-dashboard/

install

Deploying the Kubernetes Dashboard

GITHUB_URL=https://github.com/kubernetes/dashboard/releases
VERSION_KUBE_DASHBOARD=$(curl -w '%{url_effective}' -I -L -s -S ${GITHUB_URL}/latest -o /dev/null | sed -e 's|.*/||')
kubectl create -f https://raw.githubusercontent.com/kubernetes/dashboard/${VERSION_KUBE_DASHBOARD}/aio/deploy/recommended.yaml

mohanpedala

Getting Started

• Notes
  • Application troubleshooting
  • Cluster Troubleshooting
  • Docker Space issue
  • Controller-Manager
  • Cloud Controller-Manager
  • TAINT
  • Difference between Replication Controller, Replica Sets and Deployements

• ETCD

lucasrenan

kubectl get pods --all-namespaces --sort-by='.metadata.name' -o jsonpath='{.items[*].spec.containers[*].resources.limits.memory}'

kubectl get pod --all-namespaces --sort-by='.metadata.name' -o json | jq -r '[.items[] | {pod_name: .metadata.name, containers: .spec.containers[] | [ {container_name: .name, memory_requested: .resources.requests.memory, cpu_requested: .resources.requests.cpu} ] }]'