RFA MD subscriber - No quality of service

The status message "No Quality of Service is available
to process subscription, timeout expired" could be generated by RFA in these 4
situations.

1. RFA
subscribes market data from the service that is currently down

xxx Status Status: No Quality of Service is available to
process subscription, timeout expired State: 3 Status Code: 3

2. RFA
subscribes market data from the service that doesn’t exist

xxx Status Status: No Quality of Service is available to
process subscription, timeout expired State: 3 Status Code: 3

3. RFA
subscribes market data and the specified QoS doesn’t match the QoS provided by
the service

For example, the Qos of the service is real-time/tick-by-tick
but the application specifies the best and worst QoS to be lower than
real-time/tick-by-tick.

_pQoS->setBestTimeliness(rfa::common::QualityOfServiceRequest::realTime);
_pQoS->setWorstTimeliness(rfa::common::QualityOfServiceRequest::delayed);
_pQoS->setBestRate(rfa::common::QualityOfServiceRequest::justInTimeFilteredRate);
_pQoS->setWorstRate(rfa::common::QualityOfServiceRequest::slowestRate);
_pMarketDataItemSub->setRequestedQualityOfService(*_pQoS);

xxx Status Status: No Quality of Service is available to
process subscription, timeout expired State: 3 Status Code: 3

4. The most
common issue is that RFA C++ attempts to make request but the infrastructure
fails to deliver the image within the recoveryTimeout + waitTimeout interval,
RFA will mark the item "Closed Recover" (State = 4)

xxx Status Status: No Quality of Service is available to
process subscription, timeout expired State: 4 Status Code: 3

In this scenario, state is ClosedRecover (4) and
status code is NoResources (3). This could be the forth scenario. If the
application subscribes to a lot of items, you may consider tuning the value of
\Sessions\<session name>\recoverTimeout and \Sessions\<session
name>\waitTimeout in RFA configurations.