50 Essential Linux Commands Every Sysadmin Should Master

February 24, 2025 rootlogic linux

For users who want a no-nonsense, technical rundown of key Linux commands, here’s a curated list of 50 commands with fresh wording and a re-ordered sequence to boost your productivity on the command line.

pwd – Displays your current working directory.
Example:
```
pwd
```
cd – Changes your directory to the specified path.
Example:
```
cd /path/to/directory
```
ls – Lists files and folders in the current directory.
Example:
```
ls -la
```
mkdir – Creates a new directory.
Example:
```
mkdir new_folder
```
touch – Generates an empty file or updates the timestamp on an existing file.
Example:
```
touch newfile.txt
```
rm – Deletes files or directories (use with caution).
Example:
```
rm unwanted_file.txt
```
cp – Copies files or directories from one location to another.
Example:
```
cp source.txt destination.txt
```
mv – Moves or renames files and directories.
Example:
```
mv oldname.txt newname.txt
```
rmdir – Removes an empty directory.
Example:
```
rmdir empty_folder
```
cat – Outputs the content of a file to the terminal.
Example:
```
cat file.txt
```
less – Opens files in a paginated view for easier reading and backward scrolling.
Example:
```
less file.txt
```
more – Similar to less, it displays file content page by page.
Example:
```
more file.txt
```
head – Shows the first few lines of a file.
Example:
```
head -n 10 file.txt
```
tail – Displays the last part of a file; useful for log files.
Example:
```
tail -n 10 file.txt
```
find – Searches for files and directories based on specified criteria.
Example:
```
find / -name "targetfile.txt"
```
grep – Filters text or searches for specific patterns within files.
Example:
```
grep "search_term" file.txt
```
locate – Quickly finds files by name using a prebuilt database.
Example:
```
locate file.txt
```
which – Reveals the full path of shell commands.
Example:
```
which python3
```
whereis – Locates the binary, source, and manual pages for a command.
Example:
```
whereis gcc
```
chmod – Modifies file or directory permissions.
Example:
```
chmod 755 script.sh
```
chown – Changes the owner and/or group of a file or directory.
Example:
```
sudo chown user:group file.txt
```
df – Reports disk space usage of file systems.
Example:
```
df -h
```
du – Estimates the file space usage of directories and files.
Example:
```
du -sh /path/to/directory
```
free – Displays memory usage statistics.
Example:
```
free -m
```
top – Provides a real-time view of system processes and resource usage.
Example:
```
top
```
ps – Lists current running processes.
Example:
```
ps aux
```
kill – Terminates a process by its Process ID (PID).
Example:
```
kill 1234
```
killall – Ends processes by name instead of PID.
Example:
```
killall process_name
```
history – Shows a list of previously executed commands.
Example:
```
history
```
alias – Creates shortcuts for longer commands.
Example:
```
alias ll="ls -la"
```
echo – Prints text or variable values to the terminal.
Example:
```
echo "Hello, World!"
```
uname – Displays system information such as the kernel name and version.
Example:
```
uname -a
```
date – Outputs or sets the current date and time.
Example:
```
date
```
cal – Presents a simple calendar.
Example:
```
cal
```
man – Opens the manual page for other commands.
Example:
```
man ls
```
ssh – Securely connects you to a remote system over a network.
Example:
```
ssh user@hostname
```
scp – Securely copies files between hosts using SSH.
Example:
```
scp file.txt user@remote:/path/to/directory
```
wget – Retrieves files from the web via HTTP, HTTPS, or FTP.
Example:
```
wget https://example.com/file.zip
```
curl – Transfers data with URL syntax; often used for API interactions.
Example:
```
curl -O https://example.com/file.zip
```
tar – Archives multiple files into a single file, often for backup purposes.
Example:
```
tar -czvf archive.tar.gz /path/to/directory
```
gzip – Compresses files using the GNU zip algorithm.
Example:
```
gzip file.txt
```
gunzip – Decompresses files that were compressed with gzip.
Example:
```
gunzip file.txt.gz
```
zip – Combines and compresses files into a zip archive.
Example:
```
zip archive.zip file1.txt file2.txt
```
unzip – Extracts files from a zip archive.
Example:
```
unzip archive.zip
```
ping – Sends ICMP echo requests to test network connectivity.
Example:
```
ping google.com
```
traceroute – Tracks the route packets take to a network host.
Example:
```
traceroute google.com
```
netstat – Displays network connections, routing tables, and interface statistics.
Example:
```
netstat -tuln
```
ip – Manages and displays networking, replacing older tools like ifconfig.
Example:
```
ip addr show
```
sudo – Executes commands with superuser privileges.
Example:
```
sudo apt-get update
```
apt-get – Handles package management for Debian-based systems.
Example:
```
sudo apt-get install package_name
```