Trouble Shooting

There are several ways to troubleshooting Usage Engine and solutions deployed on it. 

Debug Printouts 

Debug from Workflows can be viewed directly in the Workflow Monitor or be sent to a file. Debug is turned on/off in the Workflow Monitor UI, or by using CLI commands. There are standard events for some agents that will appear as debug – for example when files are collected, forwarded, and discarded, and when duplicate files and records are found. User defined debug events are defined from APL code. For each debug event, timestamp and originating node is automatically added to the message. 

System Log 

Events and errors are saved in the System Log, which is managed from DROnline. There are three categories of events originating from the Usage Engine system, from workflows, and from user activities. Besides the automatically generated logs, a user can configure system log messages from APL code. To avoid overflowing the log, duplicate messages are not repeated. The first and last occurrence is displayed, including how many times it was repeated. 

Purging of the system log is done automatically and using a predefined clean up task. The frequency is configurable. 

Data Veracity 

When unexpected things happen during processing of payload data, for instance decoding errors or unexpected type codes, Usage Engine provides a powerful subsystem called Data Veracity to help resolving the error condition. 

Data Veracity is used when UDRs and Batch files fail validation and manual intervention is needed before they can be successfully processed. Erroneous UDRs are sent to database tables, following the structure of the UDRs. 

Refer to chapter 11 (Sub Systems) for further detail on Data Veracity. 

Error Correction System (ECS) 

To preserve compatibility with configuration migrated from older MediationZone systems, Usage Engine also supports ECS as an alternative to Data Veracity. ECS does not provide as much functionality for working with erroneous data as Data Veracity. 

Refer to chapter 11 (Sub Systems) for further detail on ECS. 


Usage Engine provides inspectors to give insight into data at rest. Inspectors exist for Aggregation storage, Duplicate DUR detection, Duplicate Batch detection and Data Veracity.