Ethernet Networking Overview
Bridge manages Ethernet switch fabrics using a Day 0 / Day 1 / Day N lifecycle model. On Day 0, Bridge discovers the switch topology. On Day 1 (as part of Day 0 setup), Bridge configures the network underlay. On Day N, Bridge provisions isolated tenant overlay networks on demand as tenants are onboarded and compute is allocated.
Fabric Lifecycle
| Phase | Operation | What Bridge Does |
|---|---|---|
| Day 0 | Switch fabric discovery | Discovers all switches and compute nodes via OOB network using LLDP |
| Day 1 | Underlay configuration | Configures BGP EVPN, IP addressing, MTU, and loopback interfaces across the fabric |
| Day N | Overlay provisioning | Creates per-tenant VxLAN segments, VRFs, and ACLs on the switch fabric as tenants are created and compute is allocated |
Supported Switch Fabrics
| Switch Vendor | Platform |
|---|---|
| NVIDIA Spectrum-X | Spectrum-4 SN5000 Series with Cumulus Linux |
| Cisco | See Cisco |
Tenant Network Isolation
On an Ethernet fabric, Bridge enforces tenant isolation at two network levels:
East-West (Compute) Network
Each tenant is assigned a unique VRF and VxLAN segment for compute traffic. BGP EVPN propagates VxLAN routes across the fabric, providing L2 adjacency over an L3 spine-leaf topology.
The tenant's compute VRF is mapped to the corresponding tenant Converged VRF, enabling integrated access to storage and in-band management without cross-tenant leakage.
North-South (Converged) Network
The Converged Network carries three traffic types, all isolated per tenant:
| Traffic Type | Description |
|---|---|
| Storage | High-performance access to storage backends (VAST, DDN, WEKA, NFS) |
| In-band management | Control plane traffic for managing compute and storage resources |
| External connectivity | Outbound access and inbound tenant service exposure via the gateway |
Per-tenant VxLAN segments and VRFs are used for Converged Network isolation, with BGP EVPN propagating the mappings across the fabric.
Underlay Architecture
The underlay provides the L3 routing foundation that carries VxLAN overlay traffic:
- BGP sessions are established between leaf and spine switches.
- Loopback addresses serve as VTEP (VxLAN Tunnel Endpoint) IPs.
- MTU is configured to accommodate VxLAN encapsulation overhead.
- BGP EVPN is used as the control plane for advertising overlay routes.
Bridge creates the underlay as a single operation immediately after topology discovery. See Networking Overview for the underlay creation procedure.
Related Pages
- NVIDIA Spectrum-X — Spectrum-X switch fabric automation, SuperNIC configuration, multi-tenancy, and observability
- Cisco — Cisco Ethernet switch integration
- Networking Overview — Underlay creation procedure and full tenant isolation architecture