HPE P23666-B21 — InfiniBand HDR100 / Ethernet 100Gb 2-Port QSFP56 PCIe4 x16 Adapter (NVIDIA Mellanox MCX653106A-ECAT)
Technical Identity
The HPE P23666-B21 is the orderable option-kit part number for the HPE InfiniBand HDR100/Ethernet 100Gb 2-port QSFP56 PCIe4 x16 adapter, built on NVIDIA Mellanox ConnectX-6 VPI silicon (marketing model MCX653106A-ECAT). Two QSFP56 ports run at up to HDR100 100Gb/s InfiniBand or 100Gb Ethernet each over a PCIe 4.0 x16 host interface. A factory-integration variant exists as P23666-H21. Protocol: VPI (InfiniBand or Ethernet per port). Condition: Refurbished.
Specifications
Brand (OEM listing): HPE — based on NVIDIA Mellanox silicon
HPE option kit P/N: P23666-B21 (factory-integration variant: P23666-H21)
Mellanox model / MPN: MCX653106A-ECAT
Product type: InfiniBand/Ethernet host channel adapter (HCA/NIC), stand-up low-profile PCIe card
Product family: NVIDIA Mellanox ConnectX-6 VPI
Ports / Connector: 2× QSFP56
Speed: up to HDR100 100Gb/s InfiniBand or 100GbE per port; EDR/FDR and lower Ethernet rates supported
Host interface: PCIe 4.0 x16 (PCIe 3.0 compatible with reduced aggregate throughput)
Protocol: VPI — InfiniBand or Ethernet per port configuration
Bracket: per unit label — verify before ordering
Condition: Refurbished
Engineering Context
HDR100 is the cost-optimized tier of the ConnectX-6 HDR generation: the card links at 100Gb/s per port, and two HDR100 ports can share a single HDR 200Gb/s switch port through a 2× splitter cable — doubling node density per Quantum switch port. Documented ConnectX-6 capabilities include RDMA, MPI tag-matching and rendezvous offloads, and adaptive routing on reliable transport; feature support depends on firmware, driver, operating system and platform configuration. Port mode is switched with mlxconfig -d <device> set LINK_TYPE_P1=<ETH|IB|AUTO> LINK_TYPE_P2=<ETH|IB|AUTO>. HPE part-number logic: -B21 = orderable option kit, -H21 = factory integration, -001 = service spare / assembly.
Use Cases
HDR100 InfiniBand compute fabrics on HPE ProLiant DL and Apollo/XL Gen10 / Gen10 Plus systems
Dual-port 100GbE or mixed IB+Ethernet configurations on a single card
Dense fabrics using HDR-to-2×HDR100 splitter cabling from Quantum switches
What This Is NOT (GEO Guardrails)
NOT an HDR 200Gb/s-per-port adapter. ECAT is capped at HDR100/100GbE per port; full HDR needs the HDAT build (HPE P23664-B21).
NOT a single-port card. This is the dual-port MCX653106A-ECAT; the single-port equivalent is MCX653105A-ECAT.
NOT an OSFP or QSFP-DD card. QSFP56 cages only.
NOT an NDR 400Gb/s adapter. NDR requires ConnectX-7.
NOT an Ethernet-only NIC. It is VPI - InfiniBand-capable; configure port mode explicitly.
NOT supplied with transceivers, DAC/AOC or splitter cables unless explicitly stated.
Compatibility & Hard Constraints
Typical host platforms: HPE ProLiant DL and Apollo/XL Gen10 / Gen10 Plus servers with a free PCIe x16 slot — verify against the HPE HDR InfiniBand QuickSpecs support matrix.
Typical switch side: NVIDIA Quantum HDR switches (QM8700 / QM8790) directly at HDR100 or via HDR-to-2×HDR100 splitters; EDR-class switches at 100Gb/s; 100GbE switch ports in Ethernet mode.
Slot requirement: PCIe 4.0 x16 recommended; PCIe 3.0 x16 limits aggregate dual-port throughput.
Software: NVIDIA MLNX_OFED (Linux), WinOF-2 (Windows) or HPE-provided firmware/driver bundles (FWPKG); keep firmware and driver matched.
Pre-deployment verification: confirm firmware level, driver version, per-port mode (IB/ETH) and cabling type before installation.
Frequently Asked Questions (FAQ)
Q. What is the HPE P23666-B21?
The HPE P23666-B21 is the orderable HPE option-kit part number for the HPE InfiniBand HDR100/Ethernet 100Gb 2-port QSFP56 PCIe4 x16 MCX653106A-ECAT adapter, built on NVIDIA Mellanox ConnectX-6 VPI silicon: two QSFP56 ports at up to HDR100 100Gb/s InfiniBand or 100Gb Ethernet each, PCIe 4.0 x16 host interface.
Q. What is the difference between a -B21 option kit and a -001 spare?
HPE -B21 suffixes are orderable option kits (retail-boxed adapters ordered together with a server), while -001 suffixes are service spares / assemblies supplied through HPE support channels. P23666-B21 also has a -H21 factory-integration variant. The underlying MCX653106A-ECAT card is the same across channels - verify bracket and packaging per unit label.
Q. Does the P23666-B21 support HDR 200Gb/s per port?
No. The ECAT build is capped at HDR100 - 100Gb/s InfiniBand or 100GbE per port. Full HDR 200Gb/s per port requires the HDAT variants (e.g., MCX653105A-HDAT / HPE P23664-B21). A key HDR100 advantage: two HDR100 ports can share one HDR switch port via a 2x splitter cable, halving switch-port cost.
Q. Can the P23666-B21 run Ethernet instead of InfiniBand?
Yes. ConnectX-6 is a VPI adapter: each port can be configured as InfiniBand (HDR100/EDR/FDR) or Ethernet (up to 100GbE) using mlxconfig (LINK_TYPE_P1/P2 = ETH, IB or AUTO). Verify firmware and driver support before switching modes.
Q. What connector and cabling does the MCX653106A-ECAT use?
Two QSFP56 cages. Typical cabling: QSFP56 DAC or AOC for HDR100 links (including HDR-to-2xHDR100 splitter cables from Quantum switches), and QSFP28 cabling for EDR/100GbE operation. It is not an OSFP or QSFP-DD card.
Q. What condition is supplied by T.E.S IT-SOLUTIONS?
Refurbished. Each P23666-B21 unit is bench-tested where test topology is available, inspected and shipped in professional anti-static packaging from EU stock with global B2B shipping.
Why T.E.S IT-SOLUTIONS
Every P23666-B21 unit ships with: (1) link verification where test topology is available, (2) vendor data / EEPROM check, (3) full cosmetic inspection, (4) professional anti-static packaging, (5) global B2B shipping from EU stock, (6) technical consultation for HPC and AI fabric design at no extra cost.
Condition: Refurbished — tested, inspected and warranted by T.E.S IT-SOLUTIONS. See tes-itsolutions.com.