Hi,
I will try to answer the query from MSA storage perspective.
Any one with virtual connect expertise can answer other queries.
The best practice for physical connectivity is A1 , A2 ports (any two host ports of ontroller A) to one virtual connect and B1 , B2 ports (any two host ports of controller B)to another virtual connect.
If virtual connect does not have enough free uplink ports the recommended physical conenctivity would be A1 to one virtual connect and B1 to another virtual connect.
I would not suggest using Link aggregation. Load balancing will occur at controller host port level using the multipathing policy set on host server.
Volume is owned by a single controller in MSA and data traffic will happen only through owning controller host ports as long as owning controller host port path/controller is up.
Could you elaborate on this question?
Which type of connection to use Fabric or ethernet?
If you are referring to fibre channel connection using 10Gb iscsi SFP or DAC ethernet cable. You may choose either of them and should not make any difference. Ensure that which ever connection type is being used is supported by virtualconnect.
MSA 2050 best practices guide:
https://h20195.www2.hpe.com/v2/getpdf.aspx/A00015961ENW.pdf?