◆ RSINetworkInterfaceType

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Description:: Identifies how the RMP transmits and receives EtherCAT frames on the host NIC. On Linux, the default path is AF_PACKET (raw sockets). For lower-latency operation, AF_XDP (eXpress Data Path) bypasses most of the kernel networking stack, delivering frames directly between user space and the NIC driver via a shared UMEM ring buffer.

Enabling AF_XDP:: AF_XDP is not auto-detected. Enable it by adding <UseAfXdp/> to the <Settings> block in CustomNodeInfo.xml. See NodeInfo & CustomNodeInfo files for file details.

Fail-Closed Design:: If AF_XDP setup fails at network start, the RMP does not silently fall back to AF_PACKET. Instead it reports RSINetworkStartError::RSINetworkStartErrorAF_XDP_SETUP_FAILED (error 23) and the network will not start. This is intentional — a silent fallback would hide a misconfiguration and forfeit the latency benefit.

Runtime Check:: After a successful network start, call NetworkStatusGet and inspect the InterfaceType field to confirm which path is active.

For AF_XDP setup requirements, validated hardware, and troubleshooting, see RMP PC hardware and performance requirements.

See also: NodeInfo & CustomNodeInfo files; RMP PC hardware and performance requirements

Enumerator
RSINetworkInterfaceTypeINTIME_HPE2	INtime HPE2 real-time network interface path for EtherCAT frame transmit/receive. Windows only.
RSINetworkInterfaceTypeLINUX_AF_PACKET	Linux AF_PACKET raw socket path (packet socket) for EtherCAT frame transmit/receive. This is the default on Linux.
RSINetworkInterfaceTypeLINUX_AF_XDP	Linux AF_XDP socket path. Bypasses the kernel networking stack for lower-latency EtherCAT I/O. Requires `<UseAfXdp/>` in CustomNodeInfo.xml. See NodeInfo & CustomNodeInfo files.
RSINetworkInterfaceTypeLINUX_AF_XDP_ZERO_COPY	Linux AF_XDP zero-copy path. Like AF_XDP but eliminates the kernel-to-UMEM copy when the NIC driver supports it (e.g., Intel `igc`). Requires `<UseAfXdp/>` in CustomNodeInfo.xml.

Definition at line 1434 of file rsienums.h.