Continuing my DevOps refresh! Today, we're diving deeper into Linux commands.
While staple commands are readily available online, I'll be focusing on some hidden gems
Command:
File and Directory Handling:
tree - Shows a visual tree-like representation of the directory structure.
stat filename - Displays detailed information about a file, including permissions, size, timestamps, inode, blocks, links, and owner.
du -h directory - Estimates disk usage of a directory and its contents in a human-readable format.
find . -name "*.txt" -type f -exec grep -l "pattern" {} ; - Finds all .txt files containing a specific pattern and prints their names.
ln -s source_file link_name - Creates a symbolic link to a file (like a shortcut).
touch filename - Creates an empty file or updates the timestamp of an existing one.
Searching and Viewing Data:
tail -f filename - Continuously displays the last lines of a growing file (useful for logs).
less filename - Views a file interactively with pagination and search capabilities.
grep "pattern" filename - Searches for a pattern within a file and prints matching lines.
awk '{print $2, $4}' filename - Processes a file by fields and extracts desired information.
sed 's/old/new/g' filename - Performs text replacement within a file (e.g., for substitutions).
System Information and Monitoring:
top - Displays real-time information about running processes and resource usage.
htop - An enhanced version of top with a visual interface and more interactive features.
free - Shows available and used memory in the system.
df -h - Shows disk usage and free space for mounted filesystems.
ps -aux - Lists information about all running processes.
Network Troubleshooting:
ping hostname - Checks connectivity to a remote host by sending ICMP echo requests.
traceroute hostname - Traces the path taken by packets to reach a remote host, identifying network hops.
netstat -tulpn - Lists active network connections and listening ports.
dig domain.com - Queries DNS information for a domain.
Text Manipulation and File Editing:
sort filename - Sorts lines of a text file alphabetically or numerically.
uniq filename - Removes duplicate lines from a text file.
head filename - Prints the first few lines of a file.
tail filename - Prints the last few lines of a file.
tee filename - Redirects output to both a file and the terminal.
Stay tuned for these lesser-known powerhouses in my blog post, and feel free to share your favorite under-appreciated commands in the comments below!