====== 15.4 Node Logs ======

[[fxdemo:05-part:start | Go To Top ]]

[[fxdemo:05-part:15-logging-and-observability:start | Return to Logging and Observability ]]

Each [[dido:99_annexes:annex-b-terms-and-definitions:n:node|Node]] should produce logs that explain its [[dido:99_annexes:annex-b-terms-and-definitions:l:lifecycle|Lifecycle]] and runtime behavior. Node logs should support diagnosis, review, and acceptance of [[dido:99_annexes:annex-b-terms-and-definitions:e:evidence|Evidence]].

Node logs should record:

  - Node startup.
  - Configuration source.
  - Node Identity and role.
  - [[dido:99_annexes:annex-b-terms-and-definitions:d:dds|DDS]] participant initialization.
  - Publisher and subscriber initialization.
  - Topic participation.
  - Lifecycle state changes.
  - Status publication.
  - Command receipt and command result, where applicable.
  - Data Plane publication or subscription events, where applicable.
  - Warnings and degraded conditions.
  - Recoverable and non-recoverable errors.
  - Controlled shutdown.
  - Exit result.

Node logs should align with [[dido:99_annexes:annex-b-terms-and-definitions:c:control_plane|Control Plane]] status messages. If a Node publishes Running status, its logs should show the successful startup path that led to Running. If a Node publishes Failed status, its logs should identify the failure condition. If logs and status messages disagree, the team should treat that disagreement as a defect or open issue.

Node logs should use the file header and inline documentation conventions defined in Section 7.10 where logging functions, logging wrappers, or logging configuration files require explanation.

----

<WRAP centeralign>

© 2026 Dido Solutions, Inc. and Jackrabbit Consulting, Inc.

</WRAP>