damarco wrote:But this should work, the links to the DF AVB are two separate networks. The DF AVB does not require any backup functionality. The question is how the technical MIC12 is implemented? If this should set up two Rudunate streams according to Milan, the hardware is able to set up one stream per port.
Technically the secondary port should have the same functionality. With Dante hardware, the behavior can be set, switch mode etc.
Yes, technically you are right - my recommendation against it comes from a usability perspective.
MILAN redundancy provides a failover when one of two (totally separate) networks fails. An ATDECC controller that is aware of this (such as Hive) can create a "single" stream connection between two devices (that implement Milan redundancy and have two ports) simultaneously on PRI and SEC ports, even if the controller itself is connected to only one of the two networks. This means that Hive will "hide" half of the streams and give you separate icons/colors/shapes in the matrix for redundant devices. If you disconnect one port, Hive will show you* a network failure on the corresponding port, but the listener will still receive all the audio from the talker over the other network.
*Hive will show you nothing if it was controlling the entities on the network you just disconnected, of course...
Using the primary and secondary port to connect two separate entities is possible (although I do not recommend it, see above), and I am aware that this is a valid use case. It might not work with a redundancy-aware controller like Hive, but it does currently work with the RME AVB Controller which shows separate streams for the primary and secondary port as a consecutive list. You have to do the logic yourself to remember which streams of the remote entity (ie. 12Mic) are available on the entity that you are running the controller on (one of the Digifaces). Since PRI and SEC ports are not bridged, you only see and control only half of the connections and need to use two Digiface AVB controllers (one to manage the PRI connections on computer 1, and one to manage the SEC connections on computer 2).
So, connect Digiface AVB 1 to PRI and Digiface AVB 2 to SEC. Both will see the 12Mic and enumerate 18 stream sources and 18 stream sinks, but you can only use half of those: on the Digiface AVB 1, you stream from and to "Primary" streams 1-9 (labeled as "P" or Primary) and on the Digiface AVB 2, you stream from and to "Secondary" streams 1-9 (labeled as "S" or Secondary). The 12Mic should be clock master, the Digiface AVB 1 synchronized to any of the Primary incoming connected streams, and the Digiface AVB 2 synchronized to any of the secondary incoming connected streams.
The Primary and Secondary streams coming from the 12Mic carry the exact same audio information, so yes, you can use this to connect two computers and record the same audio. The Primary and Secondary streams going to the 12Mic are selected in a similar manner as the MADI Auto Input.
. The main question is that of the clock.