Hello,
The logs generated by your application will be stored in the Azure Log Analytics Workspace in a table with the name you defined when you configured the custom log collection, followed by _CL
Now that you have that data in this table in the Azure Log Analytics Workspace, you can use the Kusto Query Language (KQL) to write a query that will find the exceptions you want to alert on, then just create an Azure Monitor Alert with that KQL Query as logic.
More info:
- Getting started with KQL
- Creating an Azure Monitor Alert from a KQL Query
- Configure Actions on Azure Monitor Alerts (ex: email notifications)
I hope it helps!
BR,
George