help with iperf and infiniband and multiple NIC

I have two Dell servers in a rack in my server room: - **RHEL 7.9 x86-64** and **iperf-2.0.13-1.el7.x86_64** - hostnames are A and B - each has - 1 10GbE intel nic, having 2 ports - 1 1Gbps intel nic {traditional} having 2 ports - 1 mellanox infiniband card - my network naming is - em1, 10GbE port 1 - em2, 10GbE port 2 - em3, 1Gbps port 1, **static ip 192.168.1.1 / 255.255.255.0** - em4, 1Gbps port2 - ib0, mellanox infiniband 100 gbps, **static ip 192.168.2.1 / 255.255.255.0** - A is 192.168.x.1 and B is 192.168.x.2 where x = 1 for 1Gbps and x = 2 for infiniband - I can ping between each and also scp between either on the infiniband 192.168.2.x subnet. On A if I simply do iperf -s and on B I do iperf -c 192.168.1.1 is works and says 942 mbits/sec. But on B if I do iperf -c 192.168.2.1 I get no route to host. How do I use iperf in this scenario to see the transfer speed over specific network interfaces? Specifically my ib0? And eventually over my em1 10GbE when I get that set up?