The Replication - Undistributed Commands alarm becomes active when the number of undistributed commands exceeds a threshold.
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Undistributed commands are commands in the distribution database that have not been delivered to the selected subscriber.

When this alarm occurs, look at the history of the affected subscription.

  1. Open the Activity drilldown | Subscriptions page and select the affected subscription.
  2. Select a session from the Sessions of the Log Reader Agent grid.
  3. The informational and error messages logged for that session are shown in the Top 200 Actions grid.

If you select a merge publication in the Subscription grid, the Sessions grid is displayed. Selecting a session displays the Session Articles grid.