DevOps Cheat Sheets Collection #

Quick Reference Cards for All Master Classes
Essential commands and patterns at your fingertips

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Docker Cheat Sheet #

# Images
docker pull nginx
docker build -t myapp:v1 .
docker images
docker rmi image-id

# Containers
docker run -d -p 80:80 nginx
docker ps
docker stop container-id
docker rm container-id
docker logs container-id
docker exec -it container-id bash

# Cleanup
docker system prune -a

# Compose
docker-compose up -d
docker-compose down
docker-compose logs -f

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Kubernetes Cheat Sheet #

# Pods
kubectl get pods
kubectl describe pod pod-name
kubectl logs pod-name
kubectl exec -it pod-name -- bash
kubectl delete pod pod-name

# Deployments
kubectl create deployment nginx --image=nginx
kubectl scale deployment nginx --replicas=3
kubectl rollout status deployment/nginx
kubectl rollout undo deployment/nginx

# Services
kubectl expose deployment nginx --port=80 --type=LoadBalancer
kubectl get svc

# Namespaces
kubectl get ns
kubectl create ns production
kubectl config set-context --current --namespace=production

# Config
kubectl apply -f deployment.yaml
kubectl get all
kubectl describe deployment nginx

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Git Cheat Sheet #

# Setup
git config --global user.name "Name"
git config --global user.email "email@example.com"

# Basic
git init
git clone url
git status
git add .
git commit -m "message"
git push
git pull

# Branching
git branch
git branch feature
git checkout feature
git switch -c feature
git merge feature
git branch -d feature

# Undo
git reset --soft HEAD~1
git reset --hard HEAD~1
git revert commit-hash

# Remote
git remote -v
git remote add origin url
git push -u origin main

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Terraform Cheat Sheet #

# Init
terraform init
terraform init -upgrade

# Plan & Apply
terraform plan
terraform plan -out=tfplan
terraform apply
terraform apply tfplan
terraform apply -auto-approve

# Destroy
terraform destroy
terraform destroy -target=resource

# State
terraform state list
terraform state show resource
terraform state rm resource

# Format & Validate
terraform fmt -recursive
terraform validate

# Workspaces
terraform workspace list
terraform workspace new prod
terraform workspace select prod

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Ansible Cheat Sheet #

# Ad-hoc
ansible all -m ping
ansible all -m shell -a "uptime"
ansible webservers -m apt -a "name=nginx state=present" --become

# Playbooks
ansible-playbook playbook.yml
ansible-playbook playbook.yml --check
ansible-playbook playbook.yml --tags "config"
ansible-playbook playbook.yml --limit webservers

# Inventory
ansible-inventory --list
ansible-inventory --graph

# Vault
ansible-vault create secrets.yml
ansible-vault edit secrets.yml
ansible-vault encrypt file.yml
ansible-vault decrypt file.yml

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Prometheus PromQL Cheat Sheet #

# Rate
rate(http_requests_total[5m])

# Sum
sum(rate(http_requests_total[5m])) by (endpoint)

# Percentile
histogram_quantile(0.95, rate(http_request_duration_seconds_bucket[5m]))

# Availability
avg_over_time(up[24h])

# Top K
topk(5, sum(rate(http_requests_total[5m])) by (endpoint))

# Error rate
rate(http_requests_total{status=~"5.."}[5m])

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AWS CLI Cheat Sheet #

# EC2
aws ec2 describe-instances
aws ec2 start-instances --instance-ids i-xxx
aws ec2 stop-instances --instance-ids i-xxx

# S3
aws s3 ls
aws s3 cp file.txt s3://bucket/
aws s3 sync dir/ s3://bucket/dir/

# IAM
aws iam list-users
aws iam create-user --user-name john
aws iam create-access-key --user-name john

# EKS
aws eks list-clusters
aws eks update-kubeconfig --name cluster-name

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Linux Commands Cheat Sheet #

# Files
ls -la
cd /path
pwd
mkdir -p dir
rm -rf dir
cp source dest
mv old new
find . -name "*.txt"
grep "pattern" file

# Permissions
chmod 755 file
chown user:group file
umask 022

# Processes
ps aux
top
htop
kill pid
killall process

# System
df -h
du -sh *
free -h
uptime
systemctl status service
journalctl -u service -f

# Network
ip addr
ss -tulpn
ping host
curl url
wget url

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Shell Scripting Cheat Sheet #

# Variables
NAME="value"
echo $NAME
echo ${NAME}

# Conditionals
if [ condition ]; then
    echo "true"
fi

# Loops
for i in {1..10}; do
    echo $i
done

while [ condition ]; do
    echo "loop"
done

# Functions
function name() {
    echo "Hello $1"
}

# Arrays
ARR=("a" "b" "c")
echo ${ARR[0]}
echo ${ARR[@]}

# Special vars
$0  # Script name
$1  # First argument
$#  # Number of arguments
$@  # All arguments
$?  # Exit status
$$  # Process ID

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Python DevOps Cheat Sheet #

# File operations
from pathlib import Path
Path('file.txt').read_text()
Path('file.txt').write_text('content')

# Run commands
import subprocess
result = subprocess.run(['ls', '-la'], capture_output=True, text=True)

# AWS boto3
import boto3
s3 = boto3.client('s3')
s3.list_buckets()
s3.upload_file('local.txt', 'bucket', 'remote.txt')

# Kubernetes
from kubernetes import client, config
config.load_kube_config()
v1 = client.CoreV1Api()
v1.list_namespaced_pod('default')

# HTTP requests
import requests
response = requests.get('https://api.example.com')
data = response.json()

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Database Cheat Sheet #

PostgreSQL #

-- Connect
psql -U user -d database

-- Databases
CREATE DATABASE mydb;
\l
\c mydb

-- Tables
CREATE TABLE users (id SERIAL PRIMARY KEY, name VARCHAR(50));
\dt
\d users

-- Queries
SELECT * FROM users;
INSERT INTO users (name) VALUES ('John');
UPDATE users SET name = 'Jane' WHERE id = 1;
DELETE FROM users WHERE id = 1;

MongoDB #

// Databases
show dbs
use mydb

// Collections
db.users.insertOne({name: "John"})
db.users.find()
db.users.updateOne({name: "John"}, {$set: {age: 30}})
db.users.deleteOne({name: "John"})

// Indexes
db.users.createIndex({name: 1})

Redis #

# Strings
SET key "value"
GET key
DEL key

# Hashes
HSET user:1 name "John"
HGET user:1 name
HGETALL user:1

# Lists
LPUSH mylist "item"
LRANGE mylist 0 -1

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🎓 DevOps Cheat Sheets Collection Complete