Voltaire VLT-30112 — Grid Director 4036 36-Port QSFP QDR 40Gb/s InfiniBand Switch, 1U
Technical Identity
The Voltaire VLT-30112 is a part number in the Voltaire Grid Director 4036 series — a 1U InfiniBand switch with 36 QSFP ports at QDR 40Gb/s per port. The verified 4036 platform delivers 2.88Tb/s of non-blocking bandwidth with 100ns port-to-port latency and includes embedded device and subnet management, adaptive routing and congestion management. Voltaire was acquired by Mellanox Technologies in 2011 and the 4036 line was subsequently sold under Mellanox branding. Protocol: InfiniBand QDR. Condition: Refurbished.
Identity note: the specific VLT-30112 build is not confirmed against original Voltaire documentation. Reseller catalogue data describes it as a single-PSU 4036 with front-to-back cooling, but that is channel data, not a vendor specification. PSU count, airflow direction and management/licence level are VLT-30112 variant attributes and must be confirmed per unit label.
Specifications

Brand: Voltaire (later Mellanox Technologies)
Model / P/N: VLT-30112
Platform: Voltaire Grid Director 4036
Product type: InfiniBand switch, fixed configuration
Ports: 36 x QSFP
Port speed: QDR 40Gb/s per port
Non-blocking bandwidth: 2.88Tb/s
Port-to-port latency: 100ns
Protocol: InfiniBand QDR (IBTA)
Management: embedded device and subnet management on the 4036 platform
Fabric features: adaptive routing, congestion management
Form factor: 1U rack-mount
PSU count / airflow: VLT-30112 variant per unit label
Condition: Refurbished

Engineering Context
QDR InfiniBand runs 10Gb/s per lane over four lanes with 8/10 encoding, giving the 40Gb/s per-port rate quoted for the Grid Director 4036 and therefore for the VLT-30112. That is a different generation from FDR10 (40Gb/s, 64/66 encoding), FDR (56Gb/s), EDR (100Gb/s), HDR (200Gb/s) and NDR (400Gb/s) — a QDR switch cannot be firmware-upgraded to a higher generation. The 4036 was positioned as a single-rack fabric switch whose embedded subnet manager and adaptive routing let a cluster run without an external SM host. T.E.S also lists VLT-30011, VLT-30013, VLT-30034 (4036E edge) and VLT-30111 — all 4036 family, all separate listings.
Use Cases

Single-rack QDR 40Gb/s InfiniBand fabric for legacy HPC compute clusters.
Cold spare or like-for-like replacement for an installed Grid Director 4036 / VLT-301xx switch.
Lab, test and university cluster fabrics where QDR bandwidth is sufficient.

What This Is NOT

NOT an FDR, EDR, HDR or NDR switch. Maximum per-port rate is QDR 40Gb/s. FDR 56Gb/s requires SwitchX-2, EDR requires Switch-IB, HDR requires Quantum, NDR requires Quantum-2.
NOT an Ethernet switch. The Grid Director 4036 is InfiniBand only. Voltaire’s Ethernet line is the Vantage series (for example VLT-30065 Vantage 6048).
NOT a QSFP+ FDR, QSFP28, QSFP56 or OSFP switch. QSFP QDR cages only.
NOT the same listing as VLT-30011, VLT-30013, VLT-30034 or VLT-30111. Those are separate Grid Director 4036 part numbers with their own configurations.
NOT confirmed as a single-PSU or dual-PSU unit. PSU count and airflow direction of a VLT-30112 must be read from the unit label — do not assume either.
NOT supplied with QSFP transceivers, DAC/AOC cables, rail kits or spare power supplies.

Compatibility & Hard Constraints

Typical fabric endpoints: QDR 40Gb/s QSFP InfiniBand host adapters of the Mellanox ConnectX-2 generation and equivalent OEM-branded QDR HCAs.
Typical cabling: QSFP QDR passive copper DAC and QDR active optical cable. Verify cable profile recognition in the switch management interface.
Software: embedded Voltaire switch software / subnet manager on the switch; an OFED-class driver stack on hosts. Current MLNX_OFED and DOCA releases have dropped this generation — confirm the driver matrix for the target OS.
Rack and power: 1U plus rails. PSU count and airflow direction must be confirmed from the unit label and matched to the rack cooling plan.
Pre-deployment verification: exact VLT-30112 configuration on the unit label, firmware level, subnet-manager and licence state, PSU population, airflow.

Frequently Asked Questions (FAQ)
Q. What is the Voltaire VLT-30112?
VLT-30112 is a part number in the Voltaire Grid Director 4036 series: a 1U InfiniBand switch with 36 QSFP ports at QDR 40Gb/s per port, 2.88Tb/s non-blocking bandwidth and 100ns port-to-port latency.
Q. Is the exact VLT-30112 configuration confirmed?
No. The 4036 platform specification is verified, but the specific VLT-30112 build — PSU count, airflow direction and management level — must be read from the unit label. T.E.S can photograph and confirm the label before dispatch.
Q. What speed does the VLT-30112 run?
QDR 40Gb/s per port across 36 QSFP ports. It is not an FDR 56Gb/s, EDR 100Gb/s, HDR 200Gb/s or NDR 400Gb/s switch and cannot be upgraded to those generations.
Q. Can the VLT-30112 run Ethernet?
No. The Grid Director 4036 is an InfiniBand-only platform. Voltaire’s Ethernet products belong to the separate Vantage switch line.
Q. How does VLT-30112 relate to VLT-30034 and VLT-30013?
All are part numbers within the Grid Director 4036 family, differing in configuration — VLT-30034 is the 4036E edge variant. T.E.S stocks them as separate listings; they are not interchangeable without checking each unit label.
Q. Does the VLT-30112 include a subnet manager?
The 4036 platform includes embedded device and subnet management. The management and licence state actually enabled on an individual VLT-30112 should be verified before it is relied on in production.
Q. What condition is supplied by T.E.S IT-SOLUTIONS?
Refurbished. Each VLT-30112 is powered up and inspected where test topology is available, with port and management checks, cosmetic inspection and anti-static packaging. EU stock, global B2B shipping.
Why T.E.S IT-SOLUTIONS
Every unit ships with: (1) power-on and management verification where test topology is available, (2) firmware and label check, (3) cosmetic inspection, (4) anti-static packaging, (5) global B2B shipping from EU stock, (6) technical consultation for InfiniBand fabric design at no extra cost.
Condition
Condition: Refurbished. Pre-owned legacy hardware, cleaned, inspected and tested by T.E.S IT-SOLUTIONS. End-of-life platform, supplied without vendor warranty or manufacturer support entitlement; no current NVIDIA or Mellanox support contract applies.