🧵 Kubernetes Troubleshooting Series:

Scenario: Pod stuck in ImagePullBackOff or ErrImagePull?

Here’s a step-by-step thread to troubleshoot and fix it like a pro. 💡

#Kubernetes #DevOps #Containers 1/ Why does this happen?

When a pod can’t pull the container image, it may get stuck in ImagePullBackOff or ErrImagePull.

This commonly occurs due to:
- Private Docker registries 🏰
- Wrong image names/tags ❌
- Expired or missing imagePullSecrets 🔐

🐧 AWK Master Cheat Sheet: 15 Must-Know Commands for DevOps & Linux Admins 🖥️ 1️⃣ Basic Print

Print the first column of a file:
awk '{print $1}' file.txt

👉 Extracts and prints the first field from each line.

🚀 7-Day Docker Learning Series – Day 7: Docker Security Best Practices 🛡️ Welcome to the final day of our Docker Learning Series! Today, we’ll focus on Docker Security – essential for protecting your containers, images, and infrastructure.

🚀 7-Day Docker Learning Series – Day 6: Docker Compose – Managing Multi-Container Applications 🛠️ Welcome to Day 6 of our Docker Learning Series! Today, we’ll learn about Docker Compose, a powerful tool to define and manage multi-container applications using a simple YAML file.

🔹 Why Use Docker Compose?

🧵👇 (Thread)

🚀 7-Day Docker Learning Series – Day 5: Docker Networking – Connecting Containers 🌐 Welcome to Day 5 of our Docker Learning Series! Today, we’ll dive into Docker Networking, how containers communicate, and different network types.

🔹 Why is Docker Networking Important?

🧵👇 (Thread)

🚀 7-Day Docker Learning Series – Day 4: Docker Volumes – Managing Data in Containers 📦

Welcome to Day 4 of our Docker Learning Series! Today, we’ll learn how Docker handles data using volumes. 🔹 Why Do We Need Docker Volumes?

🧵👇 (Thread)

🚀 7-Day Docker Learning Series – Day 3: Dockerfile – Build Your Own Docker Images 🐳 Welcome to Day 3 of our Docker Learning Series! Today, we’ll learn how to create custom Docker images using a Dockerfile.

🔹 What is a Dockerfile?

🧵👇 (Thread)

🚀 7-Day Docker Learning Series – Day 2: Docker Images & Containers 🐳 Welcome back to Day 2 of our Docker Learning Series!
Today, we dive deep into Docker Images & Containers, the backbone of Docker.

#Docker #DevOps #Cloud

🚀 7-Day Docker Learning Series – Day 1: Introduction to Docker 🐳

Welcome to the Docker Learning Series! Whether you’re a beginner or looking to refresh your knowledge, this series will help you understand Docker step by step. 🔹 Day 1: What is Docker? Why Use It?

🧵👇 (Thread)

Docker Interview Guide!

A thread with 20+ mid-level to advanced Docker interview questions and answers 🐳 1/ What is a Docker Compose, and why is it useful? 🚢

A. Docker Compose is a tool for defining and running multi-container Docker applications. It's useful for managing complex applications with multiple services, enabling easy orchestration. #Docker #Interview

Kubernetes Interview Guide!

A thread with 20+ mid-level to advanced Kubernetes interview questions with concise answers 🚢📷 📷👇 1/ 🚀 Q: What is Kubernetes and why is it essential for container orchestration?

A: Kubernetes is an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications, ensuring high availability and reliability.

🧵 How to Start Learning Linux for DevOps Aspirants 🚀🐧

From newbie to pro in no time!
Let’s make Linux your ultimate superpower. 🦸‍♂️🦸‍♀️ 1/ Start with the Basics 🛠️✨
• Discover Linux distros: Ubuntu 🟣, CentOS 🔵, Red Hat 🔴.
• Set up Linux in a VM (VirtualBox/VMware 💻).
• Get cozy with the terminal – your new BFF! 🖥️👊

🐧 Linux Networking Commands: 10 Daily-Used Examples (Thread) 🧵 1/ ifconfig (Deprecated: Use ip):
Check & configure network interfaces.

ifconfig eth0 up # Enable interface
ifconfig eth0 down # Disable interface

Use ip instead:
ip addr show eth0
ip link set eth0 up

#LinuxNetworking #SysAdmin

Platform Engineer vs. SRE vs. DevOps Engineer!

A Thread 🧵 1/ What’s the difference? 🤔
All these roles focus on improving software delivery and reliability but have different goals. Here’s a quick breakdown:

AWS service limitations to keep in mind!

A List of critical #AWS services and their limitations 👇 1. EC2 – Instance limits by region, instance type restrictions.
2. RDS – Max database storage limits, instance size restrictions.
3. S3 – Max object size is 5TB, bucket policies can limit access.
4. EBS – Volume size max of 64TB, 20,000 IOPS for io1/io2 volumes.

Mastering Ansible command line!

A Thread of 10 key #Ansible commands and concepts all #DevOps and #Linux Administrators should focus on 👇👇 1️⃣ Check Ansible Version

Command:
ansible --version

Explanation:
Verify your Ansible installation and check version details.

🧵 Mastering Docker Troubleshooting: 15 Key Tips for Developers and DevOps Engineers!

A Thread 👇👇 1/ 🐳 Check Container Status
Use docker ps -a to view all containers and their statuses. A container may have exited unexpectedly.
Look at STATUS and RESTART policies to identify potential issues.

🧵 Mastering Dockerfile: A Breakdown of 15 most important Parameters!

A thread 👇👇 1️⃣ FROM:
The first instruction in any Dockerfile. It defines the base image for subsequent instructions.

FROM ubuntu:20.04 - Starts with an Ubuntu 20.04 image.

🧵 Kubernetes Security Master Guide! 🔐 1️⃣ Role-Based Access Control (RBAC)

📜 Limit access with RBAC! Define who can do what in your cluster by setting up roles and bindings. Keep permissions tight!

Example:
kubectl create rolebinding developer --clusterrole=edit --user=dev@example.com -n dev-namespace

🧵 Kubernetes Master Guide!

15 Must-Know Concepts with Examples! 🚀 1️⃣ Kubernetes Overview:
K8s is like the conductor of an orchestra, managing containerized apps across multiple machines. 🎻

Example: You have a web app, API, and database, all in different containers—K8s ensures they play in harmony. 🎶

🧵 Docker Master Guide!

15 Must-Know Concepts with Examples! 1️⃣ Containers vs. VMs
Containers are lightweight & share the host OS, while VMs are heavier, with separate OS instances.

Example:
Container: 10 MB
VM: 1 GB
Save resources with Docker containers!