Welcome back to my #DevOpsJourney! In Day 1, we covered system monitoring, networking, and file management. Today, we’ll master process control, text processing, and automation tools—the secret sauce of DevOps efficiency!
Think of these commands like kitchen gadgets 🍳—each saves time and effort, so you can focus on cooking up great infrastructure!
⚙️ 4. Process Management – Controlling Running Apps
16 . kill – The Process Terminator
What it does: Stops misbehaving processes.
Real-life analogy: Force-quitting a frozen app on your phone.
When to use:
- When a program hangs or consumes too much CPU.
- Pro Tip: Find PIDs with ps aux | grep .
17 . killall – Bulk Terminator
What it does: Kills processes by name.
Real-life analogy: Turning off all lights in a room with one switch.
When to use:
- When multiple instances of a service need restarting.
18 . bg & fg – Multitasking Wizards
What they do:
bg resumes a paused job in the background.
fg brings it back to the foreground.
Real-life analogy:
bg → Minimizing YouTube to work.
fg → Bringing it back to watch.
When to use:
19 . jobs – Background Task Manager
What it does: Lists background/suspended jobs.
Real-life analogy: Checking your to-do list sticky notes.
When to use:
- Managing long-running tasks (e.g., backups).
📜 5. Text Processing – Data Manipulation
20 . sed – The Text Surgeon
What it does: Finds/replaces text in files or streams.
Real-life analogy: Find & Replace All in a Word doc.
When to use:
- Editing config files in bulk.
- Removing empty lines: sed '/^$/d' file.txt.
- awk – The Data Scientist
What it does: Extracts and processes structured data (e.g., logs, CSVs).
Real-life analogy: Filtering Excel columns for analysis.
When to use:
- Parsing server logs.
- Calculating sums: awk '{sum+=$1} END {print sum}' data.txt.
22 . cut – The Column Cutter
What it does: Extracts specific columns from text.
Real-life analogy: Cutting coupons from a newspaper.
When to use:
- Processing CSV/TSV files.
23 . tr – The Character Translator
What it does: Replaces/deletes characters.
Real-life analogy: Converting lowercase to uppercase with a button.
When to use:
- Sanitizing inputs (e.g., removing spaces).
🔗 6. File Linking & Archives
24 . ln – The Shortcut Creator
What it does: Creates hard/soft links (like Windows shortcuts).
Real-life analogy:
Hard link: A mirror (same file, two names).
Soft link: A GPS shortcut (points to original).
When to use:
- Linking config files across directories.
25 . tar – The File Packer
What it does: Combines files into a tarball (.tar.gz).
Real-life analogy: Zipping clothes into a suitcase.
When to use:
- Creating backups.
26 . zip/unzip – Cross-Platform Archiver
What it does: Compresses to .zip format.
Real-life analogy: Packing files for email attachments.
When to use:
- Sharing files with Windows users.