How do a loop back test with single card installed?

Infrastructure & Networking Switches and Gateways InfiniBand/VPI Switch Systems
1

I have connect-6 modules installed however currently i am attempting to use loopback test only. Can anyone shed light on this on how to perform loopback test on single card with no cable attached? I am fairly well versed with ethernet but infinityband is my first foray into it by doing belows:

So far I am looking at perf_test GitHub - linux-rdma/perftest: Infiniband Verbs Performance Tests and compiled successfully which produced several types of binary: ib_write/read_bw/ etc.

Apparently one of them has loop back binary and produced following output:


[nonroot@localhost bin]$ ./run_perftest_loopback  0 1 ./ib_write_bw -s 10
 Port number 1 state is Down
 Couldn't set the link layer
 Couldn't get context for the device
 Port number 1 state is Down
 Couldn't set the link layer
 Couldn't get context for the device
[nonroot@localhost bin]$
2

Hello g900nvda,

Thank you for posting your inquiry on the NVIDIA Developer Forum - Infrastructure and Networking - Section.

Unfortunately, this is not possible when running on a single port. You need to have a dual-port adapter for doing this as it needs a SM running on one of the ports and a physical layer between the two ports to have an active link up.

Thank you and regards,
~NVIDIA Networking Technical Support

3

I actually see the card had two physical ports. But under Linux i see two devices one as Ethernet other one is ib. I am not sure two pcie devices had one to one mapping to logistical ports. I am not sure as well if it is possible to set either of them as either ib or Ethernet.