Phase 1 Scripting Review: Bash, Python & sys_report | Zero to LLMOps (Day 28)

Day 28 of a free 180-day DevOps course. Welcome back to Zero to LLMOps! Today concludes Week 4 with our Phase 1 Scripting Review milestone. Over the last six days, we evolved from basic shell scripting into enterprise automation with set -euo pipefail, getopts, and ShellCheck, then built system telemetry tools with Python standard library (argparse, os, pathlib, subprocess). Today is dedicated to deliberate practice: active recall, cold lab redos, project health auditing, and state consolidation before our timed RHCSA mock exam. What we cover today: • Cumulative Quiz (10 Questions): Covering variable quoting, pipeline failure traps, getopts option parsing, Python mutability, context managers, exception safety, and subprocess security. • Deliberate Practice Protocol: Cold redo of the week's most demanding lab (boot_logger.sh or sys_report.py) and logging syntax gaps to gap-week4.txt. • Project Ecosystem Health Check: Running boot_logger.sh -v and sys_report.py -v cleanly under the unprivileged svc_fresher account. • Static Analysis & Web Verification: Passing ShellCheck with 0 warnings, verifying rsync delta backups, and validating Nginx HTTP 200 OK responses. • Milestone Archiving: Documenting week4-state.txt inventory and creating fresher_project_day28.tar.gz backup snapshot. • Production Postmortem & LLMOps: Why an unchecked Bash wrapper masked a crashed Python collector for 2 weeks, and the dual Bash-Python architecture powering GPU cluster orchestration. ⏱ Chapters 00:00 Intro: Week 4 Review & Roadmap 01:29 Quiz Part 1: Bash Automation & Script Robustness 01:41 Q1: Double Quoting "$var" vs Word Splitting 02:04 Q2: set -euo pipefail Breakdown Piece by Piece 02:37 Q3: ShellCheck SC2086 Explained 02:52 Q4: getopts "o:vh" Options & $OPTARG 03:14 Q5: Python Data Structures: List vs Tuple Mutability 03:32 Quiz Part 2: Python Systems Automation 03:39 Q6: Context Managers: with open() Descriptor Safety 03:51 Q7: Exception Handling: Specific vs Bare except 04:11 Q8: Secure Process Execution: List vs shell=True 04:30 Q9: Path Manipulation: pathlib "/" Operator 04:44 Q10: Telemetry Inspection: sys_report.py Sections 05:24 Deliberate Practice: Cold Lab Redo Protocol 06:43 Project Health Audit: Running boot_logger.sh -v 07:28 Telemetry Tool Verification: sys_report.py -v 08:12 Static Analysis: ShellCheck Verification 08:38 Remote Synchronization: rsync Delta Transfer 08:52 Web Endpoint Health: Nginx HTTP 200 & Port 80 Debug 09:39 Milestone Archive: week4-state.txt & Tarball Backup 10:41 Production Incident: Silent Python Crash Masked by Bash 11:44 LLMOps: Bash & Python Symphony in GPU Clusters 12:13 Definition of Done & Day 29 Mock Exam Preview Definition of Done: 1. Attempted all 10 cumulative quiz questions honestly before reviewing answers. 2. Redid weakest lab (boot_logger.sh or sys_report.py) cold and logged syntax gaps in ~/lab-notes/gap-week4.txt. 3. Verified both boot_logger.sh -v and sys_report.py -v run cleanly under svc_fresher. 4. Confirmed ShellCheck passes with zero warnings on /opt/fresher_project/boot_logger.sh. 5. Confirmed rsync delta transfer succeeds and Nginx returns HTTP 200 on /report.html. 6. Created ~/backups/fresher_project_day28.tar.gz and refreshed ~/lab-notes/week4-state.txt. 7. Completed 1-3-7-21 spaced repetition catch-up (Days 27, 25, 21, and 7). 📚 FREE COURSE MATERIAL — every lesson, lab and answer key: https://github.com/mahadikabhijeet/ze... All 185 written lessons, labs, and study guides are on GitHub, free and open. ◀ Previous — Day 27: Python III (Modules, Argparse, OS/Pathlib & sys_report.py) ▶ Next — Day 29: RHCSA-Style Mock Skills Day (Timed 90-Min Practical Exam) 🔔 Subscribe for the full path from zero to LLMOps. #DevOps #Linux #Bash #Python #SysAdmin #ShellCheck #Automation #SRE #LearnPython #RHCSA #LLMOps #ZeroToLLMOps