SuperNIC
When a BlueField-3 (BF3) card is configured in NIC mode, it operates as a SuperNIC — a high-performance SmartNIC with full Spectrum-X networking capabilities. Bridge uses SuperNIC mode to configure BF3-equipped servers for participation in NVIDIA Spectrum-X high-performance GPU networking.
SuperNIC vs. DPU Mode
In NIC mode, the BF3 card does not act as an independent host control plane. The host manages the SuperNIC through the DOCA Management Service Daemon (DMSD), which Bridge uses as the configuration interface.
| Aspect | SuperNIC (NIC mode) | DPU (DPU mode) |
|---|---|---|
| Control plane location | Host | DPU |
| Managed via | DOCA DMSD on host | DPF over OOB |
| Network capability | Spectrum-X (RoCE, adaptive routing) | HBN, VRF, VTEP |
| Primary use case | High-performance GPU-to-GPU networking | Tenant isolation, distributed GW |
Prerequisites
Before Bridge configures a server as a SuperNIC host, the following conditions must be met:
- BF3 card is in NIC mode.
- DOCA Host Packages are installed on the host.
- The DOCA Management Service Daemon (DMSD) is running on the host.
Bridge's provisioning flow handles DOCA package installation and DMSD startup automatically as part of host commissioning.
Spectrum-X Configuration Flow
Bridge configures SuperNIC hosts in the following sequence:
- Install DOCA Host Packages — Bridge installs the required DOCA packages on the host via Ansible, enabling key services and libraries.
- Start DMSD — Bridge brings up DMSD on the host. DMSD acts as the control point for the SuperNIC.
- Configure Spectrum-X capabilities — Using DMSD, Bridge configures the BF3 SuperNIC with the following features:
| Feature | Description |
|---|---|
| RoCE | RDMA over Converged Ethernet for low-latency GPU-to-GPU communication |
| Congestion control | Adaptive congestion control for high-utilization AI workloads |
| Adaptive routing | Dynamic path selection to balance load across the rail-optimized topology |
| IP routing | Host IP routing configuration for Spectrum-X fabric participation |
After this sequence, the server is fully Spectrum-X aware and ready for high-performance GPU-to-GPU networking. Multi-tenancy is enforced by the BGP EVPN control plane on NVIDIA Cumulus Linux and Spectrum-X switches.
In-Band Configuration Interface
Unlike DPU mode (which uses the OOB network for management), Bridge configures the SuperNIC over the tenant-isolated in-band network using DMSD:
- Network: 400 GbE East-West fabric (in-band)
- Interface: Bridge SuperNIC controller → DMSD on host → BF3 SuperNIC
SuperNIC configuration occurs after the switch fabric underlay and tenant overlay networks are established.
Related Pages
- NVIDIA Spectrum-X — Full Spectrum-X switch fabric automation and multi-tenancy
- BlueField-3 (BF3) — DPU mode for zero-trust provisioning and HBN
- DOCA Catalog — DOCA services used by Bridge