GreenRay AIO lab helper — stands in for a physical/UI action, not a real tool

Usage: reseat-cable <node> <hca>

Ask the data-centre technician to reseat the InfiniBand cable of one HCA
port: unplug the transceiver and fibre on the adapter and on the matching
switch port, inspect and clean the connectors, and plug them back in.
The result is reported the way the technician would (port LED colour).

Arguments:
  <node>        cluster node name, as used with ssh
  <hca>         RDMA device of the port, e.g. mlx5_0

Options:
  --help        show this help and exit
