This page describes what to do in case of an Icinga alert. For more information you could search the govuk-puppet repo for the source of the alert
Email Alert API: Incomplete digest runs
Incomplete digest runs (digest_runs)
This means that there are some digest runs which haven’t been processed within the time we would expect.
digest_runsunprocessed for over 20 minutes
digest_runsunprocessed for over 1 hour
See the DigestEmailGenerationWorker for more information.
Check which digest runs are affected
DigestRun.where("created_at < ?", 1.hour.ago).where(completed_at: nil)