message: Better error when libfabric defaults to or is specified an improper FABRIC_IFACE
diff: @@ -293,6 +293,11 @@ static void init_fabric(struct fabric_state *fabric, struct _SstParams *Params,
  Svcs->verbose(CP_Stream, DPCriticalVerbose,
  "accessing domain failed with %d (%s). This is fatal.\n",
  result, fi_strerror(result));
  + fprintf(
  + stderr,
  + "SST RDMA Dataplane failure. fi_domain() has failed, which may "
  + "mean that libfabric is defaulting to the wrong interface. Check "
  + "your FABRIC_IFACE environment variable (or specify one).\n");
  return;
  }
  info->ep_attr->type = FI_EP_RDM;
  