📋 Day 17: Linux and Git/GitHub Cheat Sheet

Finally!! 🎉

You have completed the Linux & Git-GitHub hands-on tasks, and I hope you have learned something interesting from it. 🙌

Now, let's create an interesting 😉 blog that will benefit the DevOps community!

💻 Linux Commands Cheat Sheet

📂 File and Directory Operations

ls: List files and directories in the current directory.
cd <directory>: Change the current directory.
pwd: Print the current working directory.
mkdir <directory>: Create a new directory.
rmdir <directory>: Remove an empty directory.
touch <file>: Create an empty file or update the timestamp of an existing file.
cp <source> <destination>: Copy files or directories.
mv <source> <destination>: Move or rename files or directories.
rm <file>: Remove files.
cat <file>: View the content of a file.

📝 File Permissions

chmod <permissions> <file>: Change file or directory permissions (e.g., chmod 777 <file>).
chown <user>:<group> <file>: Change the owner and group of a file.

🔎 Viewing and Searching

cat <file>: Display the contents of a file.
less <file>: View the content of a file page by page.
grep <pattern> <file>: Search for a specific pattern in a file.
find <directory> -name <filename>: Search for a file by name in a directory.

🖥 System Monitoring

top: Display real-time system processes.
ps: Display currently running processes.
df -h: Show disk space usage in a human-readable format.
free -m: Display memory usage in megabytes.

🌐 Networking

ifconfig: Display network interfaces and IP addresses.
ping <host>: Send ICMP echo requests to check connectivity to a host.
netstat: Display network connections, routing tables, and interface statistics.

📦 Package Management

apt update: Update package list (Debian/Ubuntu).
apt upgrade: Upgrade installed packages (Debian/Ubuntu).
yum update: Update packages (CentOS/RHEL).
yum install <package>: Install a package (CentOS/RHEL).

🔄 Process Management

kill <PID>: Terminate a process by PID.
killall <process_name>: Terminate all processes with a specific name.
nice -n <priority> <command>: Run a command with a specific priority.

🛠 Shell Scripting

nano <script.sh>: Edit a script file using the Nano text editor.
./script.sh: Execute a shell script.
echo "text": Print text to the terminal.

📂 Archiving and Compression

tar -cvf <archive.tar> <files>: Create a tar archive.
tar -xvf <archive.tar>: Extract a tar archive.
gzip <file>: Compress a file using gzip.
gunzip <file.gz>: Decompress a gzip file.

⚙️ For more advanced commands, like AWK, GREP and SED, please refer my Advanced Linux blog :)

🛠 Git and GitHub Commands Cheat Sheet

🌱 Getting Started with Git

git init: Initialize a new Git repository in the current directory.
git config --global user.name <Name> and git config --global user.email <Email>: Used to configure git and to help it recognize out machine.
git clone <repo_url>: Clone a repository into a new directory.

📂 Working with Files

git add <file>: Add a file to the staging area.
git add .: Add all changes in the current directory to the staging area.
git commit -m "message": Commit changes in the staging area with a descriptive message.
git status: Show the working tree status.
git diff: View changes between the working directory and the staging area.

🔍 Viewing History

git log: Show the commit history.
git log --oneline: Show the commit history in a condensed, one-line format.

🔄 Undoing Changes

git restore <file_name>: Discard changes in the working directory.
git reset <file_name>: Unstage a file without losing its changes. Not recommended to do.
git revert <commit_hash>: Create a new commit that undoes the changes of a specific commit.

🌿 Branching

git branch: List branches.
git branch <branch_name>: Create a new branch.
git checkout <branch_name>: Switch to an existing branch.
git switch <branch_name>: Another way to switch branches.

🔗 Merging & Rebase

git merge <branch_name>: Merge a branch into the current branch.
git rebase <branch_name>: Reapply commits from the current branch onto another branch.

🔄 Syncing with Remote

git remote add origin <repo_url>: Add a remote repository.
git push origin <branch_name>: Push changes to the remote repository.
git pull origin <branch_name>: Fetch and merge changes from the remote repository.

📂 GitHub Basics

git fork: Create a copy of a repository on your GitHub account.
git clone <forked_repo_url>: Clone the forked repository.
git push origin <branch_name>: Push changes to your forked repository.
Pull Request (PR): After pushing changes to GitHub, create a PR to merge changes into the original repository.

🔗 Github Advanced commands

git cherry-pick <commit_id>: Used to merge a particular commit from one branch to another rather than merging the complete branch.
git stash <branch_name>: Reapply commits from the current branch onto another branch.

🔑 SSH Setup

ssh-keygen -t rsa -b 4096 -C "your_email@example.com": Generate a new SSH key.
eval "$(ssh-agent -s)": Start the SSH agent.
ssh-add ~/.ssh/id_rsa: Add your SSH private key to the agent.

This bog covers the essentials of working with Linux, Git and GitHub, focusing on the most frequently used commands. 📝. I hope this helps, for any queries please feel free to reach me out on Linkedin :)