Default Rule Target
The target of the default routing rule is the same as the supported targets of any other existing routing rule. This indicates that the target can be a service, an event, or an echo. Similarly, the response from the default routing rule target service can be forwarded or returned to the original caller. If the target service returns a fault, then the fault is handled in the same way as it is handled in any other routing rule.
Note:
If exceptions occur while evaluating or executing other routing rules, then the default routing rule is not executed.