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G. Change quiz

Read the examples first.

A developer must raise a timeout in a production service. Which of the following parts of the change process satisfy P64 (Versioning and change review)?

Select all that apply.

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  • Correct: The change is a pull request that states why the timeout changes.. Correct. P64 asks for a review of the technical basis before each change, so the reason is part of the change record.
  • Correct: A second engineer reviews the safety impact and approves the change.. Correct. P64 asks for an impact review and an approval for each change.
  • Correct: The teams that run the service are told before go-live.. Correct. P64 says to inform the affected people before go-live.
  • Incorrect: The developer edits the live setting and commits it afterwards.. Wrong. A manual change in production is the P64 violation (drift). The deployed state must match an approved commit, not the other way round.
  • Incorrect: The change is split into three smaller steps with a check between them.. Wrong. Small steps with checks belong to P65 (Small verified steps). P64 does not ask for them, and they do not replace a change review.
An audit compares a production server with its repository. Which of the following findings break P64 (Versioning and change review)?

Select all that apply.

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  • Correct: The running configuration matches no approved commit.. Correct. P64 requires that the deployed state matches an approved commit.
  • Correct: The runbook changed in production, but no version of it exists.. Correct. P64 says to version every artifact, and a runbook is an artifact.
  • Correct: A change record lists its basis and approval but no impact review.. Correct. P64 needs basis, impact review and approval in every change record.
  • Incorrect: The latest release went to 5 % of users before it went to everyone.. Wrong. A staged rollout is P65 (Small verified steps) and it does not breach P64.
  • Incorrect: The release has no trigger level that starts an automatic rollback.. Wrong. A missing trigger level is a P68 (Observational method) gap. P64 asks about versions, review and approval.
A team replaces the payment service. The change carries risk for every customer. Which of the following plans apply P65 (Small verified steps)?

Select all that apply.

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  • Correct: Send 1 % of traffic to the new service and check errors, then 10 %, then 100 %.. Correct. P65 asks for small steps and a check of each result before the next step.
  • Correct: Mark the check before 100 % as a hold point that a lead must approve.. Correct. P65 asks for each check to be marked as a hold point or a witness point.
  • Incorrect: Switch all traffic at once and keep the old service as a backup.. Wrong. Switching all traffic at once is the P65 violation. A backup does not limit how much harm the one big step can do.
  • Incorrect: Review the change once and then deploy it in one step.. Wrong. One review is P64 (Versioning and change review). P65 adds small steps with a check between them.
  • Incorrect: Roll out in steps, but decide whether to check only after step three.. Wrong. P65 asks for a check of each step before the next one starts.
A rollout plan has two checks. At check A, work stops until a lead approves. At check B, an engineer watches the metrics while the rollout continues. Which of the following statements are right?

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  • Correct: Check A is a hold point under P65.. Correct. P65 defines a hold point as a check where work stops until the check is approved.
  • Correct: Check B is a witness point under P65.. Correct. P65 defines a witness point as a check where work continues while the check is observed.
  • Incorrect: Check B is a hold point, because someone watches it.. Wrong. Under P65 a hold point stops work. Watching while work continues is a witness point.
  • Incorrect: Check A is a trigger level under P68.. Wrong. A P68 trigger level is a measured value that starts a planned backup action. A hold point is an approval that stops work.
  • Incorrect: Both checks need no marking if the steps are small.. Wrong. P65 asks for each check between steps to be marked as a hold point or a witness point.
An engineer must repair a pump that feeds a production line and that restarts itself on a signal from a controller. Which of the following actions apply P66 (Isolation before work)?

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  • Correct: Cut the power and the input flow to the pump before work starts.. Correct. P66 asks to isolate the part from all inputs and energy.
  • Correct: Lock the isolation, so nobody can restart the pump while the engineer works.. Correct. P66 asks to lock the isolation against an unexpected restart.
  • Correct: End the procedure with a step that releases the isolation.. Correct. P66 checks that a maintenance procedure starts with an isolation step and ends with a release step.
  • Incorrect: Tell the line operators that the engineer starts work at noon.. Wrong. Informing people is part of P64 (Versioning and change review). It does not stop the pump from restarting, so it is not isolation under P66.
  • Incorrect: Repair the pump in small steps and check each one.. Wrong. Small verified steps are P65. P66 asks to isolate first, so a restart cannot injure the engineer.
A product team is in week one of a two-week sprint. A senior stakeholder asks for a new feature right now. Which of the following responses fit the management form of P66 (Isolation before work)?

Select all that apply.

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  • Correct: The request waits for the next sprint.. Correct. In the management form of P66, new requests wait while the team works on its committed goal.
  • Correct: Only the Product Owner may cancel the sprint if the request is more urgent.. Correct. In the management form of P66, only the accountable owner may cancel the goal.
  • Incorrect: The stakeholder adds the feature to the sprint without discussion.. Wrong. This removes the protection of the committed goal, which the management form of P66 asks for.
  • Incorrect: The team pilots the feature with one customer first.. Wrong. A pilot is the management form of P65 (Small verified steps). It does not protect the current goal from interruption.
  • Incorrect: The team plans the feature on its critical path.. Wrong. A critical path is P67. It shapes the plan, but it does not protect the team's committed goal.
A cluster migration has five tasks. Data sync leads to DNS cutover. Documentation, a new dashboard and a load test have slack. The date is at risk. Which of the following actions apply P67 (Critical path)?

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  • Correct: Mark data sync and DNS cutover as the longest chain of dependent tasks.. Correct. P67 asks to identify the longest chain of dependent tasks.
  • Correct: Write down how much slack the other tasks have.. Correct. P67 checks that the plan marks the critical path and the slack of the other tasks.
  • Correct: Add extra people to data sync before the other tasks.. Correct. P67 asks to protect the critical path first.
  • Incorrect: Add extra people to the documentation to finish it early.. Wrong. Documentation has slack. Speeding up tasks with slack while the critical path slips is the P67 violation.
  • Incorrect: Run data sync in three small steps with a check after each.. Wrong. Small verified steps are P65. They limit harm, but they do not tell the team which tasks decide the date.
A company moves its office. Network installation must finish before the badge setup, and furniture has two weeks of slack. A supplier offers to deliver furniture earlier. What does P67 (Critical path) say?

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  • Correct: The early delivery gains nothing, because furniture has slack.. Correct. P67 says a delay on the critical path delays everything, while other tasks have slack.
  • Correct: Protect the network installation first.. Correct. P67 asks to protect the critical path first, and the network installation is on it.
  • Incorrect: Take the early delivery, because every task should finish early.. Wrong. Finishing a task with slack early does not move the end date. This is the P67 violation.
  • Incorrect: Move one department first and decide at the end of the stage whether to continue.. Wrong. This is the management form of P65 (Small verified steps). It is a different way to limit risk and does not tell you what to protect.
  • Incorrect: Drop the critical path and plan each task on its own.. Wrong. P67 asks for the longest chain of dependent tasks to be identified, not dropped.
A team ships a service whose real load is unknown until it runs in production. Which of the following parts of a plan apply P68 (Observational method)?

Select all that apply.

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  • Correct: The design fits the most probable load.. Correct. P68 asks to design for the most probable conditions.
  • Correct: The real error rate is monitored in production.. Correct. P68 asks to monitor the real values.
  • Correct: The error rate has a trigger level that starts an automatic rollback.. Correct. P68 checks that each monitored value has a trigger level and a planned backup action.
  • Incorrect: The team designs for the worst conceivable load and monitors nothing.. Wrong. P68 asks to measure the real values instead of guessing them in advance.
  • Incorrect: The team watches the error rate and decides on a rollback after go-live.. Wrong. Discovering at go-live that no rollback plan exists is the P68 violation. The backup action is planned in advance.
A programme has set a time tolerance for a data migration. It is 10 % past that tolerance. Which of the following responses fit the management form of P68 (Observational method)?

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  • Correct: The steering group decides on scope, as planned in advance.. Correct. In the management form of P68, the programme escalates and applies a planned response when a tolerance will be breached.
  • Correct: The programme monitors progress against its tolerances.. Correct. The management form of P68 asks to monitor and to escalate when a tolerance will be breached.
  • Incorrect: The programme invents a response now, because none was planned.. Wrong. P68 asks for tolerances and planned responses in advance, before the work starts.
  • Incorrect: The programme ends the stage and decides whether to continue.. Wrong. A decision at the end of each stage is the management form of P65 (Small verified steps). P68 reacts to a tolerance breach, whenever it happens.
  • Incorrect: The programme removes the tolerance, so it is no longer breached.. Wrong. A tolerance is set in advance and monitored. Removing it hides the measurement that P68 depends on.
An organization moves 30 teams to a new CI system. Which of the following plans apply P69 (Guided change)?

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  • Correct: A written reason, a named leading group and a communication plan.. Correct. P69 checks that a large change has a written reason, a named leading group and a communication plan.
  • Correct: A pilot team provides early wins that are planned and visible.. Correct. P69 asks to plan early visible wins.
  • Correct: The old system is switched off only when all teams use the new one.. Correct. P69 asks to continue until the new way is part of daily routine, and the end criterion is that the old way is switched off.
  • Incorrect: A manager announces the change by email and declares it done.. Wrong. Announcing a change by email and declaring it done is the P69 violation.
  • Incorrect: Each team receives a reviewed pull request for its pipeline change.. Wrong. A reviewed change is P64 (Versioning and change review). It covers the technical change, not how people adopt the new way of working.
A company will replace its ticket tool for all staff. A pipeline change moves the tool's configuration into git. Which of the following statements are right?

Select all that apply.

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  • Correct: P64 covers the reviewed, versioned configuration change.. Correct. P64 asks for each change to be versioned, reviewed and approved.
  • Correct: P69 covers making the need visible and leading the people through the change.. Correct. P69 applies where many people change how they work, and it asks for a leading group and communication.
  • Incorrect: P64 replaces P69, because an approved change needs no communication plan for the staff.. Wrong. P64 only requires informing the affected people before go-live. P69 adds a plan that continues until the change is routine.
  • Incorrect: P69 replaces P64, because a leading group approves the configuration.. Wrong. A leading group does not replace the P64 record of basis, impact review and approval for each change.