Question

A DevOps team manages a CloudFormation StackSet that deploys a baseline security stack to 120 member accounts across 4 regions. During a recent rollout, a malformed template caused stack operations to fail in dozens of accounts before the team noticed, forcing a lengthy manual cleanup. The team wants future rollouts to halt automatically as soon as failures begin, while still deploying to a few accounts at a time to validate changes before broad propagation. Which combination of StackSet operation preferences achieves this?

Accepted Answer

Set FailureToleranceCount to 0 and MaxConcurrentCount to a small value (e.g., 2), and set RegionConcurrencyType to SEQUENTIAL.

Answer

Set MaxConcurrentPercentage to 100 and FailureTolerancePercentage to 100 so all accounts update simultaneously and errors surface at once.

Answer

Enable automatic deployment and set FailureTolerancePercentage to 50 so half the accounts must fail before the operation stops.

Answer

Set RetainStacks to true and increase MaxConcurrentCount to 20 so failed stacks are preserved for inspection while deploying quickly.