#ScheduledTrigger does not fire on schedule

#Problem Description

After creating a ScheduledTrigger, no PipelineRun (or other resources inside the TriggerTemplate) appears at the expected time.

#Root Cause Analysis

Common reasons include:

1. The cron expression or optional timeZone is invalid, or the next tick has not yet occurred in the expected region.
2. The referenced TriggerTemplate (or inline template content) cannot be resolved, often because of a wrong name/namespace or missing permissions.
3. Rendering succeeds but creating the Tekton resources fails due to RBAC issues or validation errors in the template.

For a field-by-field explanation of the ScheduledTrigger spec, see the ScheduledTrigger API and Important Parameter Explanations.

#Problem Investigation

Always start with:

# Replace with your ScheduledTrigger name and namespace
kubectl describe scheduledtrigger <name> -n <namespace>
# Events:
#   Type     Reason                  Age               From               Message
#   ----     ------                  ----              ----               -------
#   Warning  UnknownTriggerTemplate  2s (x11 over 7s)  scheduled-trigger  failed to resolve TriggerTemplate: error getting TriggerTemplate missing-trigger-template: TriggerTemplate.triggers.tekton.dev "missing-trigger-template" not found

The Events section shows warnings such as UnknownTimeZone, UnparseableSchedule, InvalidSchedule, UnknownTriggerTemplate, or FailedCreate. Use those event types to pick the right fix from the sections below.

Follow these checks to narrow down the issue:

#Validate the schedule and time zone

1. Inspect the schedule with kubectl get scheduledtrigger <name> -n <namespace> -o jsonpath='{.spec.schedule}' and confirm it is the intended cron expression (minute hour day-of-month month day-of-week).
2. If spec.timeZone is set, confirm that it is a valid time zone (for example Asia/Shanghai). Typos cause the controller to emit UnknownTimeZone warnings and skip executions. When cron syntax is wrong the controller creates UnparseableSchedule or InvalidSchedule events; correct the expression and reapply.
3. Compare kubectl get scheduledtrigger <name> -n <namespace> -o jsonpath='{.status.lastScheduleTime}' with the current time to verify whether the most recent run is actually overdue. Remember that cron expressions are evaluated in the chosen time zone, not the viewer's local clock.

#Confirm the TriggerTemplate reference

1. When using spec.triggerTemplate.ref, ensure the referenced TriggerTemplate exists in the same namespace: kubectl get triggertemplate <ref> -n <namespace>.
2. For inline templates, run kubectl describe scheduledtrigger <name> and look for validation errors that mention missing fields inside triggerTemplate.
3. Make sure any placeholders like $(context.datetime) are only used in spec.params. The rendered template must reference them via $(tt.params.<name>); using context placeholders elsewhere causes rendering to fail and surfaces as UnknownTriggerTemplate warnings.

#Check events for apply or permission failures

1. Run kubectl describe scheduledtrigger <name> -n <namespace> and review the Events section. Messages such as FailedCreate, ResourceApplyFailed, or RBAC forbidden errors indicate the controller tried to fire but was blocked.
2. FailedCreate warnings typically mean Tekton rejected the rendered resource. Inspect the message, adjust the template, and reapply the ScheduledTrigger.
3. To isolate template issues, try instantiating a PipelineRun or TaskRun directly from the TriggerTemplate content. Manually replace every $(tt.params.<name>) placeholder with a concrete value, apply the resource, and confirm whether it creates successfully.

#Additional Tips

• When debugging, temporarily change spec.schedule to run every minute (for example */1 * * * *) to confirm whether executions start after adjustments.

• Keep the ScheduledTrigger and TriggerTemplate in the same namespace to avoid confusion with cross-namespace references.

• Use the tekton.alaudadevops.io/scheduled-trigger-name label to list all resources created by a ScheduledTrigger. For example:

  # Replace with your ScheduledTrigger name and namespace
  kubectl get pipelinerun -n <namespace> -l tekton.alaudadevops.io/scheduled-trigger-name=<scheduled-trigger-name>
  # NAME          SUCCEEDED   REASON      STARTTIME   COMPLETIONTIME
  # demo-pr-225j6    True        Succeeded   19h         19h
  # demo-pr-22j8w    True        Succeeded   151m        151m
  # demo-pr-22jxp    True        Succeeded   4h39m       4h39m
  
  # Replace with your ScheduledTrigger name and namespace
  kubectl get taskrun -n <namespace> -l tekton.alaudadevops.io/scheduled-trigger-name=<scheduled-trigger-name>
  # NAME          SUCCEEDED   REASON      STARTTIME   COMPLETIONTIME
  # demo-tr-hbbk8    True        Succeeded   40d         40d
  # demo-tr-jddi2    True        Succeeded   14d         14d
  # demo-tr-kdq5w    True        Succeeded   14d         14d

  Replace <scheduled-trigger-name> with the name of your resource to see every PipelineRun or TaskRun emitted by that ScheduledTrigger.