InfiniBand/fibre optic cable QSFP BlueOptics X2121A-5M-N-BL 5m Male/Male

The BlueOptics X2121A-5M-N-BL is a 5 m InfiniBand/fibre optic direct attach cable with QSFP male-to-male connectors. Designed for short-range, high-speed links in rack and adjacent-rack environments, this passive 40GBase-CR4 twinax copper assembly supports 40 Gbit/s data rates and MSA-compliant QSFP connectivity. The cable is intended for use with switches, routers, storage systems and other networking hardware that support QSFP 40G direct attach connections and provides a tested, mechanical and electrical match to standard QSFP interfaces.

Advantages

The cable offers a compact, low-latency physical link for high-bandwidth interconnects, with passive twinax construction that keeps power consumption and failure points low. MSA-compliant QSFP terminations and high-quality components provide consistent interoperability with major hardware platforms. At 5 metres, the cable provides a practical reach for within-rack and adjacent-rack installations while maintaining 40G performance.

Suitable for

Key specifications

How to use

Install the QSFP connectors into QSFP ports on compatible devices, ensuring the port and device firmware support passive 40G DAC cables. Route the cable with gentle bends that respect the manufacturer’s minimum bend radius to avoid signal degradation. No external power or transceivers are required for passive operation; the connected devices must provide the required signalling and protocol support. Validate the link status via device indicators or management interfaces after insertion.

Recommendations

For reliable operation, use this cable only for short-range links within racks or between adjacent racks and confirm device compatibility with passive QSFP DACs. Avoid sharp bends and exposure to mechanical strain. If hot-plugging, follow vendor guidelines for port handling and monitoring link status in the device OS to verify full 40G operation.