If you set up the reminder function in Sitecore, and you have a Multi server setup with Content Manager and Content Delivery instances, you may run into problems with reminders not being sent.
The problem is that the TaskDatabaseAgent are running on both the CM- and the CD instance in your Sitecore setup, and if the Master database is disabled on the CD instance, the sending of the reminder will fail. In the Sitecore logfiles on the CD instance you will find log entries like this one:
ManagedPoolThread #13 14:34:25 ERROR Exception in task
Exception: System.InvalidOperationException
Message: Could not find configuration node: databases/database[@id='master']
Source: Sitecore.Kernel
at Sitecore.Diagnostics.Assert.IsTrue(Boolean condition, String message)
at Sitecore.Configuration.Factory.GetConfigNode(String xpath, Boolean assert)
at Sitecore.Configuration.Factory.CreateObject(String configPath, String[] parameters, Boolean assert)
at Sitecore.Configuration.Factory.GetDatabase(String name, Boolean assert)
at Sitecore.Tasks.EmailReminderTask.SendReminder()
at Sitecore.Tasks.TaskDatabaseAgent.Run()
ManagedPoolThread #13 14:34:25 INFO Executing email reminder task
ManagedPoolThread #13 14:34:25 INFO Parameters: <r><to>xyz@domain.net</to><txt>Påmindelse kl 13:41 - ckl</txt></r>
ManagedPoolThread #13 14:34:25 ERROR Exception in task
Exception: System.InvalidOperationException
Message: Could not find configuration node: databases/database[@id='master']
Source: Sitecore.Kernel
at Sitecore.Diagnostics.Assert.IsTrue(Boolean condition, String message)
at Sitecore.Configuration.Factory.GetConfigNode(String xpath, Boolean assert)
at Sitecore.Configuration.Factory.CreateObject(String configPath, String[] parameters, Boolean assert)
at Sitecore.Configuration.Factory.GetDatabase(String name, Boolean assert)
at Sitecore.Tasks.EmailReminderTask.SendReminder()
at Sitecore.Tasks.TaskDatabaseAgent.Run()
ManagedPoolThread #13 14:34:25 INFO Job ended: Sitecore.Tasks.TaskDatabaseAgent (units processed: )
The solution to the problem is to disable the TaskDatabaseAgent on the CD instance. This is done by setting the interval to 00:00:00 on the TaskDatabaseAgent in the web.config file.
<agent type="Sitecore.Tasks.TaskDatabaseAgent" method="Run" interval="00:00:00"/>
Once you have solved the problem, you might receive a reminder mail from each database for every item where a reminder was created in Sitecore. How to solve this problem you can read about in this
blog: Receiving the same reminder twice :)
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