Devops 60 hrs

  • DevOps bridges the gap between development and operations, fostering a culture of collaboration and continuous improvement.
  • With automation at its core, DevOps accelerates software delivery while ensuring stability, scalability, and security.
  • Adopting DevOps practices empowers teams to innovate faster, respond to change efficiently, and deliver greater value to customers.

📚 Table of Contents

🟢 Getting Started

📘 Linux Administration

🔹 Introduction to Linux

  • History and Evolution
  • Linux Distributions Overview
  • System Architecture Basics

🔹 User and Group Management

  • Creating and Managing Users
  • Group Administration
  • Switching Users and sudo Access

🔹 File System and Directory Structure

  • Linux Directory Hierarchy Explained
  • Mounting and Unmounting File Systems
  • Disk Partitioning and LVM Basics

🔹 File and Directory Permissions

  • Understanding rwx Permissions
  • chmod, chown, and chgrp
  • Access Control Lists (ACLs)
  • Special Permissions: SUID, SGID, Sticky Bit

🔹 Package Management

  • apt, yum, dnf, zypper
  • Installing, Updating, and Removing Software
  • Managing Repositories
  • Compiling from Source

🔹 Process and Service Management

  • Understanding System Processes
  • Commands: ps, top, htop, kill, nice
  • Managing Services with systemctl
  • Startup and Boot Targets

🔹 Performance Monitoring and Tuning

  • CPU, Memory, Disk, Network Monitoring
  • Identifying Bottlenecks
  • Log Analysis and Rotation

🔹 Networking Essentials

  • Network Configuration: Static & DHCP
  • Tools: ip, netstat, ss, ping, traceroute, nmap
  • Firewalls: iptables, firewalld, ufw
  • SSH Configuration and Security

🔹 Storage Management

  • Mounting Disks and File Systems
  • Logical Volume Management (LVM)
  • Filesystem Types: ext4, xfs, btrfs, etc.

🔹 Backup and Recovery

  • Tools: rsync, tar, dd
  • Scheduled Backups using cron
  • Snapshot and Restore
  • Disaster Recovery Strategy

🔹 Security and Hardening

  • User Privileges and Auditing
  • SSH Key Authentication
  • SELinux/AppArmor Basics
  • Patch Management and Vulnerability Scanning

🔹 Automation and Scripting

  • Shell Scripting Basics
  • Scheduling Tasks with cron
  • Automation of Admin Tasks

🔹 Logging and Troubleshooting

  • Using journalctl and log files
  • Boot, Network, and Service Troubleshooting
  • Rescue Mode and Recovery

🔹 Virtualization and Containers

  • KVM and VirtualBox Basics
  • Introduction to Docker and Podman
  • Linux Namespaces and Cgroups

🔐 SSL/TLS with OpenSSL

🔹 SSL/TLS Fundamentals

  • What is SSL/TLS
  • Key Concepts: PKI, Certificates, CSRs
  • TLS Handshake Overview

🔹 Certificate Generation

  • Creating Private Keys
  • Generating CSRs
  • Adding SANs with openssl.cnf
  • Creating Self-Signed Certs

🔹 Key and Cert Management

  • Formats: PEM, DER, CRT, CER, KEY
  • Extract Public Keys
  • Convert Between Formats

🔹 Certificate Validation

  • Match Cert and Key
  • View Certificate and CSR Details
  • Check Validity Periods

🔹 Advanced CSR Fields

  • Using Config Files
  • Key Usage and Extended Usage
  • SAN and Custom Extensions

🔹 Certificate Deployment

  • For Nginx, Apache, HAProxy
  • Intermediate Chains
  • Secure File Permissions

🔹 Testing SSL

  • openssl s_client
  • Cipher Suite Validation
  • SSL Labs Testing

🔹 Renewal and Automation

  • Manual vs Automated Renewal
  • certbot, acme.sh Usage
  • Renewal Hooks

🔹 Troubleshooting and Best Practices

  • Common Errors (Mismatches, Expired Certs)
  • Storage Best Practices
  • TLS Hardening

🔹 Local Development

  • Using Local CAs
  • Tools: mkcert
  • Browser Trust Configurations

⚙️ Ansible for RHEL 8/9

🔹 Introduction to Ansible

  • Overview and Architecture
  • Agentless Automation Benefits

🔹 Setup and Configuration

  • Installing via DNF
  • Configuring ansible.cfg
  • Setting up Inventory

🔹 Inventory Management

  • Static and Dynamic Inventories
  • SSH Key Authentication
  • Grouping Hosts

🔹 Package Management

  • Modules: dnf, yum, rpm
  • Enabling EPEL and Custom Repos
  • Managing RPMs

🔹 Service Management

  • service and systemd Modules
  • Enabling/Disabling Services
  • Restarting and Reloading

🔹 User and Group Tasks

  • Create/Remove Users
  • Managing SSH Keys
  • ACL and Permissions

🌱 OpenTofu (Terraform Fork)

  1. Intro to OpenTofu
    • Open-source Terraform alternative
    • Community-driven governance
  2. Why Switch
    • Licensing, transparency, neutrality
  3. Installation
    • OpenTofu CLI
    • Migration from Terraform
  4. Code Compatibility
    • Using existing Terraform HCL
  5. Providers
    • Open registry support
  6. State Management
    • Compatible backends
    • State locking and drift detection
  7. Modules
    • Reusable and shareable configs
  8. CLI Commands
    • tofu plan, tofu apply, etc.
  9. CI/CD
    • Integration in pipelines
    • GitLab, GitHub Actions
  10. Best Practices
    • Naming, modularity, Git workflows