Linux is the backbone of DevOps, powering everything from servers to cloud environments. Whether you're managing files, troubleshooting networks, or automating tasks, mastering Linux commands is essential. Here’s a list of 70 must-know Linux commands for DevOps engineers, categorized for easy reference.
1. File and Directory Management
These commands help you navigate, organize, and manage files and directories efficiently:
ls – List directory contents.
cd – Change the current directory.
pwd – Show the current directory path.
mkdir – Create a new directory.
touch – Create an empty file.
cp – Copy files and directories.
mv – Move or rename files and directories.
rm – Remove files or directories.
ln – Create hard or symbolic links.
2. Searching and Viewing Files
Quickly find and inspect files with these commands:
find – Search for files and directories.
grep – Search for patterns inside files.
cat – Display file contents.
less – View files page by page.
head – Show the first few lines of a file.
tail – Show the last few lines of a file.
3. Text Editors
Modify configuration files with these essential editors:
vi/vim – A powerful text editor for advanced users.
nano – A beginner-friendly text editor.
4. Compression and Archiving
Optimize storage and create backups with these commands:
tar – Archive and extract files.
gzip – Compress files.
gunzip – Decompress files.
5. Networking
Monitor and troubleshoot networks with these commands:
wget – Download files from the web.
curl – Transfer data between systems.
ssh – Securely log in to remote servers.
scp – Securely copy files between servers.
ping – Test network connectivity.
netstat – Display network statistics.
ifconfig – Configure network interfaces.
dig – Perform DNS lookups.
nc – Use Netcat for network debugging.
6. System Administration
Manage permissions, processes, and system resources:
chmod – Change file permissions.
chown – Change file ownership.
chgrp – Change group ownership.
ps – List running processes.
top – Monitor system performance in real-time.
kill – Terminate processes.
df – Display disk usage.
du – Estimate file or directory sizes.
free – Show memory usage.
uname – Display system information.
lsof – List open files and processes.
7. User Management
Handle user accounts and permissions:
useradd – Create a new user.
passwd – Change a user’s password.
su – Switch to another user.
sudo – Run commands as another user (usually root).
usermod – Modify user accounts.
groupadd – Create a new user group.
id – Show user and group IDs.
8. Scheduling and Automation
Automate tasks and manage job scheduling:
crontab – Schedule recurring jobs.
at – Schedule one-time tasks.
history – Show previously executed commands.
source – Run a script in the current shell.
9. File System Management
Set up and manage file systems:
mkfs – Format a new file system.
mount – Attach a file system.
umount – Detach a file system.
10. Development Utilities
Increase efficiency with these useful tools:
sed – Edit text within files.
awk – Process and analyze text data.
diff – Compare files line by line.
rsync – Synchronize files between locations.
tee – Redirect output to multiple destinations.
cut – Extract sections from text.
wc – Count words, lines, and characters in a file.
11. Security
Protect systems with these security-related commands:
ssh-keygen – Generate SSH keys for authentication.
iptables – Configure the system firewall.
ssh-agent – Manage SSH keys in memory.
12. Miscellaneous
Additional commands that streamline workflow:
alias – Create shortcuts for commands.
whois – Look up domain registration details.
uniq – Remove duplicate lines from files.
sort – Arrange text lines alphabetically or numerically.
tr – Translate or delete characters from text.
paste – Merge multiple lines of text.
Conclusion
Whether you're just starting or already deep into DevOps, these Linux commands are fundamental for efficient operations. Regular practice and experimenting with different options will help you master them. Automate repetitive tasks, integrate these commands into your scripts, and become a more effective DevOps engineer!
