noCV
BDNS-106 · Rehearse endpoint changes

Preserve application compatibility across old and new addresses

Practice briefTaskAdvanced

DNS propagation sends different clients to different service versions.

Focused work estimate
3h + prerequisites
Priority in the scenario
High
Engineering practice
Compatibility · Networking

Estimated field mix

  • Networking40%
  • API design40%
  • Quality engineering20%

Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence.

Your next step

Review it, then add it to your workspace.

The board opens an editable draft; nothing is saved until you confirm it. Sign-in and workspace permissions apply, and Demo boards remain ephemeral.

Project context

A fictional internal API is moving to a new endpoint. The team assumes DNS changes are immediate and has no rehearsal for stale clients.

Setup prerequisites

  • Create a local resolver simulator and two loopback service endpoints with synthetic DNS records; query no external infrastructure.

Preceding work

Complete these dependencies, or supply their agreed outputs before taking this ticket.

Acceptance criteria

  • Exercise the same public contract on both endpoints.
  • Preserve shared operation identity across retries.
  • Reject incompatible old/new behavior before cutover.

Implementation constraints

  • Use synthetic requests and loopback endpoints.

Verification to include

  • Complete retries across both endpoints.
  • Detect a response-contract mismatch during overlap.

Deliverables

  • Endpoint overlap checks.

Rollout and recovery

Deploy compatible service behavior before changing DNS.

Value of the work

For the engineer: Practice DNS semantics, migration timing, and network diagnosis.

For the team: Produce a migration plan that makes cache delay and endpoint compatibility explicit.

Evidence boundaries

Outcome Evidence: Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs.

Ownership Evidence: Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence.