I would like to get insights on what should be our best deployment scenario.
Consider a 3 node HSX RA where each node has 2 FC ports (2 physical ports).
Consider a FC SAN
Consider a FC storage system (providing VMware datastores)
Consider a FC Tape Library
Each node connected to the FC SAN via the two physical ports and zoned via one port to the FC storage and the other port to the Tape Library
So, each node has one path to tape library and one path to storage. This way every node (which is an MA) can write backups to tape AND also run VSA SAN transport mode backups from ESXi hosts
One or two nodes connected to the FC SAN and zoned via the two FC ports to FC Storage
The remainder node(s) connected to the FC SAN and zoned via the two FC ports to Tape Library
So, each node has two ports, either to Storage or Tape. This way I get path failover to storage and tape. But each node gets specialized in writing tape backups OR backing up VMware via SAN transport mode.
Does my doubt makes sense?
Should I make all HSX node capable of writing to tape AND backing up from storage via SAN, missing path failover?
Or, should I make the node specialized in one function (writing to tape OR backing up from SAN), having two FC paths for one of those functions?
Make all three nodes able to access Disk and Tape. You have more than enough redundancy in case of a failure. And if for some reason that happens, you still have access to all the library targets.
I can`t think of a scenario based on the details you provided that would make you isolate 1 node. To be honest, I think this would really only complicate management and configuration.