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SnapCenter does not delete SCSQL database backup due to UnobservedTaskException

Last Updated:

Applies to

  • SnapCenter Server
  • SnapCenter Plug-in for Microsoft SQL Database (SCSQL)


  • When applying a retention policy during an SCSQL backup job, unnecessary backups are not deleted
  • The job details page in SnapCenter GUI indicates that Registering Backup and Applying Retention task was completed without any error
  • SnapManagerWeb.log shows error:

ERROR SnapManagerWeb PID=[XXXX] TID=[X] UnobservedTaskException occurred
ERROR SnapManagerWeb PID=[XXXX] TID=[X] Sequence contains no elements Source: System.Core
Stack Trace:    at System.Linq.Enumerable.First[TSource](IEnumerable`1 source)
   at SnapManager.SMSCore.Policy.SmRetentionHandler.FilterBackupsforCurrentHost(List`1 backups, List`1 latestBackupComponentObjectIds)
   at SnapManager.SMSCore.Policy.SmRetentionHandler.ProcessRetention(SmRetentionSettings settings, List`1 backups, SmBackup backup, 
        List`1 latestBackupComponentObjectIds, String pgName, Int64 jobId)
   at SnapManager.SMSCore.Policy.SmRetentionHandler.Execute()
   at SnapManager.SMSCore.Backup.SmRetentionManager.StartRetention(SmBackup currentBackup, SmUserOperationContext userContext, 
   SmJob backupJob, SmPluginCode pluginCode, String pluginName)
   at SnapManager.SMSCore.Backup.SmRetentionManager.StartQueuedRetention(Int64 backupId, SmPluginCode pluginCode)
   at SnapManager.SMSCore.Backup.SmRetentionManager.ProcessQueuedRetentions()
   at System.Threading.Tasks.Task.Execute()

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