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Home > Success Center > Network Performance Monitor (NPM) > NPM - Knowledgebase Articles > Subscription failures after the re-installation of an Additional Polling Engine

Subscription failures after the re-installation of an Additional Polling Engine


When you re-install an Additional Polling Engine (APE), services on the host do not start up correctly, and the RabbitMQ queue is full on the APE host. In the Orion.InformationService.log, you can find the following error:

2017-08-28 12:28:00,610 [EasyNetQ consumer dispatch thread] ERROR SolarWinds.InformationService.ChangeBrokerEvaluator.LegacyEngine.LegacyEvaluator - (null) (null)     Subscription match handler failed with an exception. Indication: Orion.Recommendations.JobCreated, SubscriptionId: 5f209902-2feb-484c-9594-a562efc4902b, Handler: System.Action`1[SolarWinds.InformationService.Addons.PubSub.EvaluatorNotification], Exception: System.InvalidOperationException: Subscription not found. SubscriptionId: 5f209902-2feb-484c-9594-a562efc4902b


  • NPM 12.0 and later


Some tables in the database are not accurate anymore and need to be rebuilt. 


Clear subscriptions and recreate them:

  1. Stop all Orion Services on all Orion servers including Additional Polling Engines and Additional Web Server.
  2. Open the SolarWinds Orion Database Manager.
  3. Click Add default Server.
  4. Right-click the Orion Database, and select New Query.
  5. Enter the following queries:



    Delete From [dbo].[PendingNotifications]
    Delete From [dbo].[SubscriptionTags]
    Delete From [dbo].[Subscriptions]


  6. Click Execute query.    
  7. Start all Orion services for all Orion Servers.

After you have cleared the subscriptions from the SolarWinds Orion database, the error does not occur any more.

Check the tables once more over the next few days. If the issues persist, create a ticket with our support team for investigation.


Related IssueClear InformationService Subscriptions 



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