Linux Tips
Mastering Linux Management
Basic VI Editor Commands
To start vi:
Example: vi letter will open a new file called letter to edit, or if letter already exists, open the existing file.
| Command | Effect |
|---|---|
| vi filename | Edit filename starting at line 1 |
| vi +n filename | Edit filename beginning at line n |
| vi +filename | Edit filename beginning at the last line |
| vi -r filename | Recover filename after a system crash |
| vi +/pattern filename | Edit filename starting at the first line containing pattern |
Updating System Packages
To update your system packages:
Example: sudo apt-get update to update the package list, followed by sudo apt-get upgrade to upgrade all packages.
| Command | Effect |
|---|---|
| sudo apt-get update | Update the list of available packages |
| sudo apt-get upgrade | Upgrade all outdated packages |
| sudo apt-get dist-upgrade | Perform a distribution upgrade |
| sudo apt-get autoremove | Remove unused packages |
Using the Nano Editor
To edit files with nano:
Example: nano filename will open the file in the nano editor.
| Command | Effect |
|---|---|
| nano filename | Open the file in nano editor |
| Ctrl + O | Save the file |
| Ctrl + X | Exit the editor |
| Ctrl + W | Search for text within the file |
| Ctrl + K | Cut the highlighted text |
Finding Files with grep
To search for files containing specific text:
Example: grep -r ‘text’ /directory will search recursively for ‘text’ in all files within the directory.
| Command | Effect |
|---|---|
| grep ‘text’ filename | Search for ‘text’ in a file |
| grep -r ‘text’ /directory | Search recursively for ‘text’ in a directory |
| grep -i ‘text’ filename | Case-insensitive search |
| grep -v ‘text’ filename | Inverse search, show lines without ‘text’ |
Managing Processes
To manage running processes:
Example: ps aux will display a list of all running processes.
| Command | Effect |
|---|---|
| ps aux | Show all running processes |
| ps -ef | grep process_name | Search for a specific process |
| kill process_id | Terminate a process by ID |
| kill -9 process_id | Forcefully terminate a process |
| top | Display real-time process information |
Managing Users and Permissions
To manage users and permissions:
Example: sudo useradd newuser will create a new user.
| Command | Effect |
|---|---|
| sudo useradd newuser | Create a new user |
| sudo passwd newuser | Set a password for the new user |
| sudo usermod -aG group newuser | Add user to a supplementary group |
| chmod 755 filename | Change file permissions (read-write-execute) |
| chown user:group filename | Change file ownership |
Network Configuration
To configure network settings:
Example: ifconfig will display network interface information.
| Command | Effect |
|---|---|
| ifconfig | Show network interface information |
| ping hostname | Test network connection to a hostname |
| netstat -tuln | Display active listening sockets |
| ssh user@hostname | Securely log into another host |
| sudo ufw allow 22 | Allow incoming SSH connections |
Task Scheduling with Cron
To schedule tasks with cron:
Example: crontab -e will edit the user’s cron jobs.
| Command | Effect |
|---|---|
| crontab -e | Edit the user’s cron jobs |
| * * * * * command | Run a command at specific times |
| 0 2 * * * command | Run a command daily at 2:00 am |
| 5 4 * * 1-5 command | Run a command every weekday at 4:05 am |
| @reboot command | Run a command at system startup |
System Monitoring
To monitor system performance:
Example: top will provide a dynamic real-time view of the processes running on the system.
| Command | Effect |
|---|---|
| top | Display real-time system processes |
| htop | Improved version of top with color |
| vmstat | Report virtual memory statistics |
| free -m | Show memory usage in MB |
| df -h | Display disk space usage in human-readable format |
| du -sh directory | Estimate file space usage of directories |
File System Navigation
To navigate the file system:
Example: cd /path/to/directory will change the current directory.
| Command | Effect |
|---|---|
| cd /path/to/directory | Change the current directory |
| pwd | Print the current working directory |
| ls | List files and directories |
| ls -l | List files with detailed information |
| mkdir directory_name | Create a new directory |
| rmdir directory_name | Remove an empty directory |
File Manipulation
To manipulate files and directories:
Example: cp source_file destination_file will copy a file.
| Command | Effect |
|---|---|
| cp source_file destination_file | Copy a file |
| mv source_file destination_file | Move or rename a file |
| rm filename | Remove a file |
| touch filename | Create a new empty file |
| ln -s target link_name | Create a symbolic link |
| chmod 755 filename | Change file permissions |
Edward Dan
Friday 18th of October 2024
Great article! As a newcomer to the Linux world, I found the tips incredibly useful. The section on mastering basic VI editor commands was particularly helpful, as it's something I struggle with. The clear examples for updating system packages were also a lifesaver – they made the process much easier to understand.