Scenario practice for DNS, HTTP, HTTPS, Nginx, release, permission, and certificate failures on a static site VPS.
Difficulty: Applied troubleshooting
What you will test: diagnosis from symptoms, command choice, expected output, and fix checklists.
Work through concrete VPS failure scenarios: DNS answers, HTTP and HTTPS behavior, Nginx status, release paths, file permissions, stale content, and certificate renewal. Each scenario asks for the safest first inspection command before a fix.
Answers/checklists: available as page sections and downloads.
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Scenario/outcome: Create a small folder with two text files. Use pwd, ls -lah, head, and grep to answer where the files are and what each contains.
Difficulty: Applied troubleshooting
What you will test: pwd, ls, and cat tell you where you are and what file you are reading before you change anything.
Create a small folder with two text files Use pwd ls lah head and grep to answer where the files are and what each contains Open a terminal find files read output and run small inspection commands with confidence Running a command in the wrong directory Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Sketch a release layout with releases/YYYYMMDDTHHMMSSZ and current. Explain how rollback would work.
Difficulty: Applied troubleshooting
What you will test: nginx -t proves configuration syntax before reload.
Sketch a release layout with releases/YYYYMMDDTHHMMSSZ and current Explain how rollback would work Understand the path from a local HTML file to a live HTTPS page on a VPS Reloading before nginx t Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Write the sequence you would use to connect a new domain to an existing VPS, including the command that proves each step.
Difficulty: Applied troubleshooting
What you will test: dig +short domain A shows the public A record answer.
Write the sequence you would use to connect a new domain to an existing VPS including the command that proves each step Connect a domain to a VPS without guessing whether the problem is DNS Nginx or TLS Changing DNS and TLS at the same time Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Build a test directory where only the parent execute bit is wrong. Use namei -l to identify the break.
Difficulty: Applied troubleshooting
What you will test: namei -l /path/to/file walks every path component.
Build a test directory where only the parent execute bit is wrong Use namei l to identify the break Diagnose why a project file cannot be read executed or served Using chmod R 777 Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Given a failing service name, list three bounded commands you would run before opening a huge log.
Difficulty: Applied troubleshooting
What you will test: tail -80 logfile reads a bounded slice before deeper searching.
Given a failing service name list three bounded commands you would run before opening a huge log Find the relevant log lines for a recent failure without reading the whole log directory Searching the whole filesystem first Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Change one line in a sample file, inspect it with git diff, stage it, and write a commit message that describes only that change.
Difficulty: Applied troubleshooting
What you will test: git status shows what changed before you commit or deploy.
Change one line in a sample file inspect it with git diff stage it and write a commit message that describes only that change Make a small project safer to edit deploy and roll back Deploying without checking the diff Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Write a five-command disk-full triage checklist and explain what each command proves.
Difficulty: Applied troubleshooting
What you will test: df -h and df -i separate byte pressure from inode pressure.
Write a five-command disk-full triage checklist and explain what each command proves Identify whether a disk-full problem is bytes inodes journal logs Docker or deleted-open files Deleting random files before proving the owner Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Describe how you would tell apart a publickey failure from a changed host key warning.
Difficulty: Applied troubleshooting
What you will test: ssh -vvv user@host shows which authentication step fails.
Describe how you would tell apart a publickey failure from a changed host key warning Debug SSH access without exposing private keys or blindly removing known hosts entries Posting private keys Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a tiny venv, install one package, and prove which python and pip are active.
Difficulty: Applied troubleshooting
What you will test: python -V and which python show which interpreter your shell will use.
Create a tiny venv install one package and prove which python and pip are active Run a project with the intended Python interpreter and dependency set Installing with one pip and running another python Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Make a one-room prototype where a test player reaches a goal and resets.
Difficulty: Applied troubleshooting
What you will test: Write the player action in one sentence before adding systems.
Make a one-room prototype where a test player reaches a goal and resets Create a tiny game loop with input movement collision a goal and reset Building menus before the loop Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Draw a three-wire sensor connection and mark power, ground, signal, expected voltage, and measurement point.
Difficulty: Careful hands-on practice
What you will test: Disconnect power before changing wiring, then verify voltage before connecting a device.
Draw a three-wire sensor connection and mark power ground signal expected voltage and measurement point Inspect a simple controller circuit with less guesswork and fewer fried parts Moving wires while powered Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: On a simple cylinder circuit drawing, mark pump, tank, valve, actuator, relief, extend path, and retract path.
Difficulty: Careful hands-on practice
What you will test: Identify the energy source and stored-energy hazards before tracing the circuit.
On a simple cylinder circuit drawing mark pump tank valve actuator relief extend path and retract path Explain what a basic hydraulic circuit is trying to do before touching equipment Treating a schematic like a wiring diagram Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for godot input actions first pass and write what each step proves before moving to the next one.
Difficulty: Applied troubleshooting
What you will test: Create action names before binding keys.
Create a small practice case for godot input actions first pass and write what each step proves before moving to the next one Make input remapping and controller support easier later Hard-coding raw key names everywhere Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for godot collision debugging basics and write what each step proves before moving to the next one.
Difficulty: Applied troubleshooting
What you will test: Turn on visible collision shapes before changing physics code.
Create a small practice case for godot collision debugging basics and write what each step proves before moving to the next one Debug a small collision problem without rewriting the whole player controller Changing movement code before proving shapes overlap Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for game save system first draft and write what each step proves before moving to the next one.
Difficulty: Applied troubleshooting
What you will test: List the exact state that must survive closing the game.
Create a small practice case for game save system first draft and write what each step proves before moving to the next one Save and reload one small game state without inventing a full account system Saving every runtime object Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for multimeter first measurements and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Set the meter mode before touching the probes to the circuit.
Create a small practice case for multimeter first measurements and write what each step proves before moving to the next one Use a meter to answer a circuit question instead of guessing Measuring resistance on a powered circuit Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for read a datasheet first pass and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Find the part number and package before trusting a pinout.
Create a small practice case for read a datasheet first pass and write what each step proves before moving to the next one Find voltage pinout absolute maximums and typical application notes Using a similar part's pinout Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for motor driver first checks and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Disconnect the motor until logic power and driver wiring are understood.
Create a small practice case for motor driver first checks and write what each step proves before moving to the next one Bring up a small motor driver safely enough to test direction and speed Powering a motor from a microcontroller pin Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for stepper motor wiring first checks and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Find the two coil pairs before connecting the driver.
Create a small practice case for stepper motor wiring first checks and write what each step proves before moving to the next one Wire a small stepper motor without randomly swapping leads Guessing wire colors Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for cad constraints first sketch and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Define the design intent before adding every dimension.
Create a small practice case for cad constraints first sketch and write what each step proves before moving to the next one Create a simple sketch that survives later changes Fully dimensioning random geometry Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for measure fastener threads and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Clean and inspect the fastener before measuring it.
Create a small practice case for measure fastener threads and write what each step proves before moving to the next one Avoid mixing similar-looking fasteners that do not actually fit Forcing metric and imperial threads together Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for welding first safety checklist and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Confirm PPE, ventilation, and nearby combustibles before power-on.
Create a small practice case for welding first safety checklist and write what each step proves before moving to the next one Prepare a safe practice weld area before learning bead control Practicing near flammables Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for hydraulic cylinder leak first checks and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Depressurize and make the equipment safe before inspection.
Create a small practice case for hydraulic cylinder leak first checks and write what each step proves before moving to the next one Describe a cylinder leak clearly before ordering parts or disassembling equipment Putting hands near pressurized leaks Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for hydraulic pressure vs flow and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Identify whether the complaint is force, speed, heat, or noise.
Create a small practice case for hydraulic pressure vs flow and write what each step proves before moving to the next one Explain why a slow actuator and a weak actuator are not the same symptom Calling every hydraulic problem low pressure Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for robot drivetrain first prototype and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Test motors off the ground before adding load.
Create a small practice case for robot drivetrain first prototype and write what each step proves before moving to the next one Drive a platform forward backward and turn reliably Adding autonomy before manual drive works Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for sensor mounting first pass and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Write what the sensor must see before designing the bracket.
Create a small practice case for sensor mounting first pass and write what each step proves before moving to the next one Mount a sensor so it can produce useful readings after the robot moves Printing a final mount before testing position Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for small engine no-start first checks and write what each step proves before moving to the next one.
Difficulty: Careful hands-on practice
What you will test: Make the machine safe and follow the manual before inspection.
Create a small practice case for small engine no-start first checks and write what each step proves before moving to the next one Describe a no-start problem in evidence terms Replacing parts randomly Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for make an obsidian project note and write what each step proves before moving to the next one.
Difficulty: Applied troubleshooting
What you will test: Write the next physical or technical action in one sentence.
Create a small practice case for make an obsidian project note and write what each step proves before moving to the next one Keep one project note that actually helps you resume work Collecting links without decisions Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for turn a video into flashcards and write what each step proves before moving to the next one.
Difficulty: Applied troubleshooting
What you will test: Watch for decisions, warnings, and output interpretation, not just vocabulary.
Create a small practice case for turn a video into flashcards and write what each step proves before moving to the next one Make five review cards that preserve the useful lesson from a video Making cards for every sentence Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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Scenario/outcome: Create a small practice case for read a project error message and write what each step proves before moving to the next one.
Difficulty: Applied troubleshooting
What you will test: Copy the exact first error line and the command that produced it.
Create a small practice case for read a project error message and write what each step proves before moving to the next one Stop treating every error message as a wall of text Fixing the last error first Use this asset with the related ladder and project path so the note, card deck, and practice task stay attached to a concrete maker outcome..
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