Which is the best Single Open and Allow Suspect Configuration for an EMA C++ developer that doesn't want be aware of reconnecting after a connection down? In other words, to have an automatic reconnecting mechanism what is it the good choice for this parameters by the point of view of a developer that use the OmmConsumerConfig class?
In my opinion, the default value of a single open and allow suspect that EMA currently uses should support the requirement and you don't need to change it. When the connection down, EMA automatically re-connecting to the server. The stream state still open and it can receive data after the connection up and service state is up again.
There is an explanation of the behavior when you set both parameters in EMA RDM Usage Guide (EMACPP_RDMUsageGuide.pdf) provided in EMA package under folder Docs. You can find the details under section 3.4.5 Single Open and Allow Suspect Data Behavior. This section also provides a table shows how a provider can convert messages to honor the consumer’s SingleOpen and AllowSuspectData settings.
In addition to my colleague's comments above, I just wanted to check that you are also using ChannelSets - if you have access to more than one ADS server at your site.
ChannelSets allows the EMA API to try and connect to a different server if one is not available. This can happen at initial startup or even during runtime if one server goes down / becomes unavailable.