Databases Reference
In-Depth Information
In this scenario, we have already established that for a synchronous proxy service,
there is limited scope to take any corrective action. However, for services that
provide multiple endpoints, one option is to retry an alternate endpoint.
Retrying a non-responsive business service
A business service allows you to configure multiple endpoints for a service, which
it can load balance requests across (using a variety of algorithms). This can be
useful when a particular endpoint becomes nonresponsive, as we can configure
the business service to automatically retry an alternative endpoint.
When we have multiple URIs specified for an endpoint, if the initial call to an
endpoint fails, the business service will immediately attempt to invoke an alternate
URI, and it will continue to do this until it is either successful, the
Retry Count
is
reached, or all online URIs have been tried.
If, at this point, the retry count has not been reached, the business service will wait
for the duration specified by the
Retry Iteration Interval
before iterating over the
endpoints again.
Finally, you need to ensure that we set
Retry Application Errors
to
No
. Otherwise,
any SOAP Fault returned by the business service will be treated as a failure and
prompt the Service Bus to retry.
In the previous example, where we have defined two URIs, if the first call fails then
the Service Bus will immediately call the second URI. If this fails, then it will have
reached the retry limit and the underlying error will be returned to the proxy service.
If the retry count was two, then it would wait for 30 seconds before attempting one
final retry.
