deVops pathshala Blog – Notes for Me & You

  • Computer Networking refers to interconnected computing devices that can exchange date and share resource with each other. Hardware Requirements    • Etherent Card, NIC, Interface, Lan Card  • Cables (wireless/wired)  • Networking Devices (HUB/Switch/Router)  Logical Terms   • IP Address (Public,Private,static,Dynamic,Virtual)   • Mac Address   • Source & Destination Address   • Ports, Sockets  • Network Address, Broadcast Address Mac address:- Mac address is the physical address , which uniqualy identifies each devices on a given network. It’s persistent.  IP address:- IP address stand for “Internet Protocol Address”. The inetenet protocol is a set of rule for communication over the internet. • Type of IP addres   1. IPv4 (Internet Protocol Version 4)   2. IPv6 (Internet Protocol Version 6)  IPv4 = 32 bit   IPv6 = 128 bit Bit = 0,1   *IPv4 = 32 bit 4 octats...

  • Storage Type   1. Floppy disk   2. CD/DVD  3. Pendrive/Memory card  4. Harddisk--> IDE,SATA,SSD,Nvme  Disk Partitioning → Disk partitioning allows system administrators a hard drive into multiple logical stroge units, referred to as a partitions.   → The process to dividing a disk into logical areas that can be worked with separately id called partitioning.  ❖ Types of Partition Scheme   1. MBR  2. GPT LVM:- Logical Volume Manager   LVM (Logical Volume Manager) is a Linux feature that allows flexible disk management. It lets you combine multiple disks into a storage pool, create logical partitions, and resize them dynamically without downtime   • PV:- Physical Volume In LVM (Logical Volume Manager), a Physical Volume (PV) is simply a storage device (like a hard disk, SSD, or a partition) that is prepared for use in LVM. • Before using a disk in LVM, you must convert it into a PV using the pv...

  VPC:-   A VPC (Virtual Private Cloud) in AWS is a private, isolated network you create in the AWS cloud to launch and manage your resources like EC2 instances, databases, etc.  Think of it as your own private data center inside AWS, where you have full control over:   • IP address ranges (CIDR blocks)  • Subnets (public & private)   • Routing (via route tables)  • Internet access (via Internet Gateway or NAT Gateway)   • Security (via security groups & network ACLs) Example    • Suppose you rent a building (AWS Cloud).   • Inside it, you design your own office layout (VPC).   • You decide rooms (subnets), doors (gateways), and locks (security groups). Key Features of VPC    1. Isolated Environment – Your VPC is separated from other AWS users’ networks.  2. Customizable IP Range – You choose IPv4/IPv6 address range.  3. Multiple Subnets – Create public and private subnets. ...

  1. docker –version --> to check docker version   2. docker version --> to check client and host version    3. docker container run httpd --> create container foreground   4. docker container run –d httpd --> create container byground  5. docker container ls --> to show only running container    6. docker container la –a --> to show all container   7. docker ps --> to show container   8. docker container stop container name --> to stop container  9. docker container start container name --> to statr container    10. docker container rm container name --> to delete stop container    11. docker container rm –f container name --> to delete running container   12. docker container run –d –it ubuntu --> to create OS image  13. docker image ls --> to show images   14. docker container run –d –name team httpd --> naming the...

1. Docker Client: a. This is where the user interacts with Docker using commands like docker build, docker run, docker pull, etc. b. It sends these commands to the Docker Daemon.   2. Docker Daemon (dockerd):  a. This is the background service that actually performs all Docker operations like building images, running containers, and communicating with the Docker registry.  b. It listens to the Docker Client's requests and manages Docker objects.  3. Dockerfile:  a. A text file that contains a set of instructions to create a Docker image.   b. The Docker Daemon reads this file to build a Docker image using the docker build command.   4. Docker Image:  a. A read-only template that contains the application code, runtime, libraries, and dependencies.  b. This is built from the Dockerfile and used to launch containers.   5. Docker Container:   a. A running instance of a Docker image.  b. It is isola...

   Are you confused about where to start your DevOps journey? This post will help you understand the complete DevOps learning path step by step. The roadmap image below shows all the important tools and concepts you should learn to become a successful DevOps Engineer in 2025 and beyond. ✅ What this roadmap covers: The correct learning order – from basics to advanced Most essential tools every DevOps engineer must know Cloud, container, automation, and CI/CD topics Real-world skills needed for job readiness 📌 Key Learning Stages: Linux Fundamentals – The base of every DevOps journey Version Control – Git & GitHub Scripting – Shell scripting and Python basics Containers – Docker and containerization Orchestration – Kubernetes fundamentals Cloud – AWS (or any major cloud provider) Configuration Management – Ansible Infrastructure as Code – Terraform CI/CD – Jenkins, GitHub Actions Monitoring & Logging – Prometheus, Grafana, ELK stack 🎯 How to use this roadmap: Don’t try...

                                                                            USER MANAGEMENT • Types of USER 1.Root user ( UID = 0) (SHELL= Login shell /bin/bash)  2. Local user ( UID = 1000 TO 6000) (SHELL=Login shell)  3. System user ( UID = 1 TO 999) (SHELL= Nologin shell /sbin/nologin)  • Type of GROUPS  1. Primary group  2. Secondary group  /etc/passwd = A file that contains “user” information  /etc/group = A file that contains “group” information                                                  COMMANDS   1. useradd = crate a new user useradd username                       ...