RHEL

-


  1.  

  1. pwd → Show current directory

  2. ls → List files

  3. ls -l → Long listing

  4. ls -a → Show hidden files

  5. cd /home → Change directory

  6. cd .. → Go up one level

  7. mkdir test → Create directory

  8. rmdir test → Remove empty directory

  9. touch file.txt → Create empty file

  10. cp file1 file2 → Copy file

  11. mv file1 file2 → Move/rename file

  12. rm file.txt → Delete file

  13. rm -r dir → Delete directory recursively

  14. find / -name file.txt → Search file

  15. tree → Show directory tree

  16. whoami → Show current user

  17. id → Show user ID info

  18. who → Show logged-in users

  19. w → Show active users

  20. adduser user1 → Add user

  21. passwd user1 → Set password

  22. usermod -aG wheel user1 → Add user to group

  23. groups user1 → Show groups

  24. deluser user1 → Delete user

  25. su user1 → Switch user

    • Command: lsblk Notes: Lists block devices (disks, partitions).

    • Command: df -h Notes: Shows mounted filesystems and usage.

    • Command: sudo fdisk -l Notes: Lists disk partitions.

    • Command: du -sh /dir Notes: Shows total size of a directory.

    • Command: mount /dev/sdb1 /mnt Notes: Mounts a disk partition to a directory.

    • Command: umount /mnt Notes: Unmounts a mounted filesystem.

    • Command: blkid Notes: Displays UUIDs and filesystem types.

    • Command: parted /dev/sdb Notes: Partition management tool.

     CPU & Memory

    • Command: lscpu Notes: Shows CPU architecture and details.

    • Command: cat /proc/cpuinfo Notes: Detailed CPU info per core.

    • Command: free -h Notes: Displays memory usage in human-readable format.

    • Command: cat /proc/meminfo Notes: Detailed memory statistics.

    • Command: vmstat Notes: Shows CPU, memory, and I/O statistics.

     Networking

    • Command: ip addr Notes: Shows IP addresses of interfaces.

    • Command: ping google.com Notes: Tests connectivity.

    • Command: traceroute google.com Notes: Shows path packets take.

    • Command: netstat -tulnp Notes: Lists listening ports and processes.

    • Command: ss -tulnp Notes: Modern socket statistics.

    • Command: curl example.com Notes: Fetches webpage content.

    User & Permissions

    • Command: whoami Notes: Shows current logged-in user.

    • Command: id Notes: Displays UID/GID info.

    • Command: useradd student Notes: Creates a new user.

    • Command: passwd student Notes: Sets password for user.

    • Command: chmod 755 file.sh Notes: Changes file permissions.

    • Command: chown user:group file.txt Notes: Changes file owner and group.

     Services & Logs

    • Command: systemctl start httpd Notes: Starts Apache service.

    • Command: systemctl stop httpd Notes: Stops Apache service.

    • Command: systemctl status httpd Notes: Shows service status.

    • Command: journalctl -u httpd Notes: Displays logs for Apache service.

    • Command: tail -f /var/log/messages Notes: Shows live system logs.



Checking Hardware Configuration in RHEL

CPU Information

  • Command: lscpu Notes: Shows CPU architecture, cores, threads, speed.

  • Command: cat /proc/cpuinfo Notes: Detailed info per processor core.

Memory Information

  • Command: free -h Notes: Displays total, used, free memory (human-readable).

  • Command: cat /proc/meminfo Notes: Detailed memory statistics.

Disk & Storage

  • Command: lsblk Notes: Lists block devices (disks, partitions).

  • Command: df -h Notes: Shows mounted filesystems and usage.

  • Command: sudo fdisk -l Notes: Lists disk partitions.

PCI & USB Devices

  • Command: lspci Notes: Lists PCI devices (network card, graphics card).

  • Command: lsusb Notes: Lists USB devices.

System Information

  • Command: uname -a Notes: Kernel and OS details.

  • Command: sudo dmidecode | less Notes: BIOS, motherboard, and system info.

All-in-One Tools

  • Command: inxi -Fx Notes: Full hardware summary (if installed).

  • Command: sudo hwinfo Notes: Detailed hardware report (if installed).



Comments

Post a Comment

Popular posts from this blog

Computer Networking (N+)

-
Image
  Computer Network: A computer network is a group of computers and other devices connected together to share information and resources. Computer networking is the process of connecting computers and other devices together so they can communicate and share information. It's like creating a web of linked devices that can talk to each other. Benefits of Networking Resource Sharing: Imagine you have one printer and several computers. Instead of each computer needing its own printer, they can all share one through the network. This saves money and makes life easier. Communication: Think of email, chat apps, or video calls. These are all made possible by networks that connect computers and allow them to exchange messages quickly. Data Management: Instead of saving files on each individual computer, you can store them on a central server. This makes it easier to manage, back up, and access data from any device in the network. Scalability: Networks can grow with your needs. If you ad...
Read more

COMPUTER HARDWARE

-
Image
  Common Operating Machine Purposely Used for Technological and Educational Research A computer is an electronic machine that can be programmed to store, process, and retrieve data, performing tasks such as calculations, logical operations, and running applications Core Definition A computer is a programmable device that accepts input, processes it, produces output, and stores results. Modern computers are digital and electronic, capable of running programs that automate tasks. The term originally referred to humans who performed calculations, but shifted to machines as technology advanced Types of Computers Supercomputers → Extremely powerful, used for scientific simulations. Mainframes → Handle large-scale business data processing. Desktops/Laptops → Personal computing devices. Smartphones/Tablets → Portable computers with touch interfaces. Embedded Systems → Specialized computers inside appliances, cars, and medical devices. Importance of Computers Automation : Speeds up...
Read more

Operating System (OS)

-
Image
                                                                           Operating System (OS) An Operating System (OS) is a software that acts as an interface between computer hardware components and the user. Every computer system must have at least one operating system to run other programs.​ An operating system (OS) is software that acts as a bridge between computer hardware and the user. It manages hardware resources and provides essential services and a user interface, enabling other software and applications to run efficiently. Examples include Windows, macOS, Linux, and Android.   History of operating system  1940s-1950s: Early Days No formal OS existed; programs were run directly on hardware. The first rudimentary "operating systems" like GMOS (General Motors Operating System) ma...
Read more