This value is the current operational status of this internal link as observed from the Fabric Interconnect side. It matters on the same internal chassis backplane link, but the record kept on the Fabric Interconnect (switch) side rather than the IOM/server side because comparing this to the matching ServerIntFIo operState is how an admin confirms both ends of the same physical connection agree about whether it's actually up. An operState of down here on this link's fabric-interconnect side while the ServerIntFIo side shows up would be an inconsistency worth investigating rather than trusting either single reading alone.