🚀 𝗧𝗼𝗽 𝗟𝗶𝗻𝘂𝘅 𝗰𝗼𝗺𝗺𝗮𝗻𝗱𝘀 𝘂𝘀𝗲𝗳𝘂𝗹 𝗶𝗻 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 𝗳𝗼𝗿 𝗗𝗲𝘃𝗼𝗽𝘀 𝗘𝗻𝗴𝗶𝗻𝗲𝗲𝗿🚀

Linux is the backbone of cloud computing, DevOps, and system administration. Mastering these essential Linux commands can help you troubleshoot, automate, and optimize infrastructure efficiently.

🔹 Basic File & Directory Commands

1️⃣ ls – List files & directories 

2️⃣ cd – Change directory

3️⃣ pwd – Show current directory

4️⃣ mkdir – Create a directory

5️⃣ rm -rf – Remove files & directories

🔹 File Management

6️⃣ touch – Create an empty file

7️⃣ cp – Copy files & directories

8️⃣ mv – Move or rename files

9️⃣ cat – View file contents

🔟 less – Paginated file viewing

🔹 Permissions & Ownership

1️⃣1️⃣ chmod – Change file permissions

1️⃣2️⃣ chown – Change file owner

1️⃣3️⃣ umask – Set default permissions

🔹 Process Management

1️⃣4️⃣ ps – View running processes

1️⃣5️⃣ top – Monitor system performance

1️⃣6️⃣ kill – Terminate processes

1️⃣7️⃣ pkill – Kill processes by name

1️⃣8️⃣ nice / renice – Adjust process priority

🔹 Networking Commands

1️⃣9️⃣ ping – Check network connectivity

2️⃣0️⃣ netstat -tulnp – View open ports

2️⃣1️⃣ ip a – Check IP address

2️⃣2️⃣ nslookup – Query DNS records

🔹 Disk & Storage Management

2️⃣3️⃣ df -h – Check disk space

2️⃣4️⃣ du -sh folder/ – Check directory size

2️⃣5️⃣ mount – Mount filesystems

🔹 User Management

2️⃣6️⃣ whoami – Show current user

2️⃣7️⃣ id – Display user ID & group ID

2️⃣8️⃣ who – List logged-in users

2️⃣9️⃣ passwd – Change password

3️⃣0️⃣ su – Switch user

🔹 Logs & Monitoring

3️⃣1️⃣ uptime – Show system uptime

3️⃣2️⃣ dmesg – View system logs

3️⃣3️⃣ journalctl – Check systemd logs

3️⃣4️⃣ tail -f /var/log/syslog – Monitor logs live

🔹 Package Management

3️⃣5️⃣ apt / yum / dnf – Install packages

3️⃣6️⃣ rpm -q – Query installed RPM packages

3️⃣7️⃣ dpkg -l – List installed Debian packages

🔹 Advanced Commands

3️⃣8️⃣ crontab -e – Schedule tasks

3️⃣9️⃣ systemctl – Manage services

4️⃣0️⃣ tar -cvf backup.tar /dir – Create an archive

4️⃣1️⃣ grep – Search for patterns

4️⃣2️⃣ find – Locate files

🔹 Special Commands for DevOps

4️⃣3️⃣ docker ps – List running containers

4️⃣4️⃣ kubectl get pods – View Kubernetes pods

4️⃣5️⃣ ansible-playbook – Run Ansible automation scripts

🔹 Miscellaneous Commands

4️⃣6️⃣ alias – Create command shortcuts

4️⃣7️⃣ history – View command history

4️⃣8️⃣ env – Show environment variables

4️⃣9️⃣ echo $PATH – Display system path

5️⃣0️⃣ exit – Log out of a session

Basic LINUX Commands 

📂 File Management & Navigation

🔹 ls – List files and directories

🔹 ls -l – List with detailed info

🔹 ls -la – Include hidden files

🔹 cd dir – Change to directory

🔹 cd .. – Move to the parent directory

🔹 cd /dir – Change to an absolute path

🔹 cd – Go to home directory

🔹 pwd – Print current directory

🔹 mkdir dir – Create a directory

🔹 rm file – Delete a file

🔹 rm -f file – Force delete file

🔹 rm -r dir – Delete a directory

🔹 rm -rf dir – Force remove directory

🔹 cp file1 file2 – Copy file

🔹 mv file1 file2 – Rename file

🔹 mv file dir/ – Move file to directory

🔹 touch file – Create/update file

🔹 cat file – View file contents

🔹 tail -f file – View file as it updates

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🌐 Networking

🔹 ping host – Check connectivity

🔹 whois domain – Get domain info

🔹 dig domain – Get DNS records

🔹 wget file – Download file

🔹 wget -c file – Resume download

🔹 curl URL – Fetch webpage content

🔹 ssh user@host – Remote login

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⚙ System Info

🔹 date – Show date/time

🔹 uptime – System uptime

🔹 whoami – Show current user

🔹 w – Who is online

🔹 cat /proc/cpuinfo – CPU details

🔹 cat /proc/meminfo – Memory info

🔹 free – Check RAM usage

🔹 du -sh – Show directory size

🔹 df -h – Disk space usage

🔹 uname -a – Kernel info

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📦 Compression

🔹 tar -cf file.tar files/ – Create archive

🔹 tar -xf file.tar – Extract archive

🔹 tar -tf file.tar – List archive contents

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🔐 Permissions

🔹 chmod 777 file – Full access for all

🔹 chmod 755 file – rwx for owner, rx for others

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🛠 Process Management

🔹 ps – View running processes

🔹 ps aux – Detailed process list

🔹 kill PID – Kill a process

🔹 killall process – Kill all instances

🔹 grep "pattern" file – Search for text

🔹 locate file – Find a file

🔹 whereis app – Locate application

🔹 man command – Get command manual

*****Essential Linux Commands for DevOps*****

System Analysis:

• htop - Interactive process viewer with CPU, memory, and load metrics

• netstat -tulpn - Display active network connections and listening ports

• ps aux | grep - Filter and find specific running processes

• lsof - List open files and processes using them

• dmesg - Display kernel-related messages and system logs

File Management:

• find . -name - Search files recursively by name or pattern

• rsync - Efficient file transfer and synchronization tool

• tar -xvf - Extract compressed archives

• grep -r - Search text patterns recursively in files

• sed -i - Stream editor for inline text modifications

Container & Orchestration:

• docker stats - Real-time container resource usage

• docker logs -f - Stream container logs live

• kubectl get pods - List Kubernetes pod status

• crictl pods - Low-level container runtime inspection

Monitoring & Logs:

• tail -f - Follow file updates in real-time

• watch - Execute commands periodically

• vmstat - Report virtual memory statistics

• journalctl - Query systemd journal logs

Network Tools:

• curl -v - HTTP request debugging with headers

• dig - DNS lookup utility

• ss - Socket statistics

• nc - Network testing and data transfer

Performance:

• strace - Trace system calls and signals

• tcpdump - Capture and analyze network traffic

• perf - Performance analysis tools

• sar - Collect and report system activity

System Control:

• systemctl - Control systemd services and units

• chmod/chown - Manage file permissions and ownership

• du -sh - Summarize directory sizes

• screen/tmux - Terminal session management