AI & HPC networks
Why do 32 QM9700 OSFP cages represent 64 NDR ports?
Count the independent NDR services before choosing shared connector assemblies.
Counting visible modules is an unreliable way to count NDR services. A QM9700 switch cage holds a twin-port assembly, while an adapter connection may use a different physical termination and a different endpoint rate.
The short answer
Count cages, independent links and endpoint ports separately. A twin-port switch connection carries two NDR links; an NDR200 fanout has a different endpoint map. Verify the exact assembly before deriving cable or adapter quantities.
QM9700 has 32 twin-port OSFP cages serving 64 NDR ports. Count the two independent links in each cage separately. Conceptual illustration; equipment shapes are illustrative.
Official technical sources · Independent analysis by SwitchInfra
This is a documented design analysis, not a customer deployment claim. Candidate roles require verification for your configuration.
32 — physical OSFP cages
64 — NDR switch connections
Twin-port — switch-side assembly
Independent — logical link accounting
What the technical reference establishes
NVIDIA’s cabling guide describes QM9700 as a 1U switch with 64 NDR connections presented through 32 OSFP connectors. Its switch connectors require the finned form.
For a comparable purchase, create three columns: physical cage, logical link and remote endpoint. This simple separation reveals whether a proposed cable count actually reaches every purchased adapter without consuming a reserved uplink.
Switch end — Each described QM9700 cage provides dual NDR ports.
Cooling form — The switch-side OSFP assembly is finned.
Adapter end — Single-port adapter connections use a different termination.
Unknown — A final endpoint count and selected cable OPNs are not established.
Scope of the analysis: Independent selection analysis of official NVIDIA documentation. Proposed examples are not a deployed customer project or a SwitchInfra delivery.
Work through the engineering choices
Start with the documented constraint, then state the conditions for the proposed equipment role.
Draw two link records beneath each populated cage
One physical switch connector exposes two NDR links.
Design exercise: four populated cages can expose eight native NDR links.
Give the two links different identifiers and peers even when they share a module housing. An installation label should let an operator identify both the parent cage and the individual link. Otherwise a replacement request can confuse one affected service with the whole connector assembly.
Separate switch-to-switch connections from switch-to-adapter connections before totaling assemblies. A link between switches consumes a corresponding link at both ends. Count shared housings independently from logical paths, and reserve the planned fabric uplinks before spending every exposed connection on hosts.
NDR cabling components · Connecting NDR components
QM9700 family
NDR switching candidate
32 twin-port OSFP cages expose 64 NDR connections; verify offered variant.
Choose native NDR or NDR200 endpoint allocation
The guide describes two-way and four-way switch-to-endpoint assemblies.
Design exercise: Proposed task: reconcile every fanout leg with one supported remote port.
For native-rate endpoints, retain the pair of switch links as separate services. For NDR200 endpoints, establish how the switch modes and cable branches expose the required lower-width paths. A four-ended assembly does not establish that all four remote cards support the intended protocol or rate.
Record the endpoint OPN and its actual connector rather than ordering from the ConnectX family name alone. Confirm the managed configuration with the system supplier. A physical fanout drawing is necessary for procurement, but it does not replace a supported port configuration or a working fabric test.
Connecting NDR components · ConnectX-7 introduction and host requirements
ConnectX-7 NDR adapter family
400G or NDR200 endpoint inquiry
Confirm OPN, protocol, connector and supported port configuration.
Turn the link map into physical installation requirements
Switch and adapter OSFP forms serve different cage designs.
Design exercise: Proposed RFQ: include both end forms and the installation route for each assembly.
Check heat-sink form, clearance and service access at each end. Do not select a part merely because OSFP appears on both labels. For optical assemblies, specify the PMD, fiber type, connector finish and mapping separately; for copper, request the exact supported length and bend requirements.
After installation, reconcile discovered links with the planned peers and retain counter and error evidence under the agreed workload. A complete cage population is not proof of a correctly wired fabric. Keep spare assemblies identified by their full configuration so a service replacement preserves the intended map.
NDR cabling components · Connecting NDR components
NDR twin-port OSFP interconnect family
Switch-end connection inquiry
Require matching finned switch end and the correct endpoint assembly.
Quote link capacity and assembly quantity separately
The purchasing sheet should show how each shared housing becomes independent services. This avoids doubling modules in one design and undercounting remote ends in another.
Parent map
Switch cage, logical link identifiers and uplink allocation.
Endpoint map
Adapter OPN, NDR/NDR200 requirement and supported remote connector.
Assembly map
Exact cable family, end forms, branches, lengths and spare configuration.
Candidate models and selection boundaries
These are conditional model or product-family inquiries for the documented equipment roles. Confirm the required rate and complete channel before finalizing any line.
| Model / family and status | Role and condition |
|---|---|
| QM9700 family Conditional model / family inquiry | NDR switching candidate 32 twin-port OSFP cages expose 64 NDR connections; verify offered variant. NDR cabling components |
| ConnectX-7 NDR adapter family Conditional model / family inquiry | 400G or NDR200 endpoint inquiry Confirm OPN, protocol, connector and supported port configuration. ConnectX-7 introduction and host requirements |
| NDR twin-port OSFP interconnect family Conditional model / family inquiry | Switch-end connection inquiry Require matching finned switch end and the correct endpoint assembly. Connecting NDR components |
Official model or family references only. Exact SwitchInfra listings, offered configuration, supply and project compatibility have not been verified; request confirmation by model.
Continue in the relevant product family
Use the analysis to define the role before comparing catalog options.
Discuss this project
Carry the route, media, endpoint and loss requirements into the inquiry. Leave unknown quantities blank; reference port and fiber counts are not an equipment BOM.
Follow the next selection question.
Compare related decisions while keeping each source’s scope, hardware and link conditions separate.
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Before you finalize the channel
Is each OSFP cage one NDR port?
Not for the described QM9700 arrangement: each presents two NDR links.
Does a twin-port module create one 800G application link?
The housing contains separate links; application aggregation requires its own design.
Can a flat adapter OSFP replace the switch assembly?
Do not infer interchangeability. The documented switch cage uses the finned form.
Do four fanout legs guarantee four working endpoints?
No. Verify endpoints, switch mode, cable mapping and fabric operation.
Trace the project facts and technical limits
Source check: 19 October 2026. Catalog status is stated per candidate.
Official sources read 19 October 2026. Project-specific engineering review, firmware support, exact offered parts and supply remain unconfirmed.