UCSC-C240-M7SX Technical Architecture and Ent
Hardware Architecture and Core Component Specifications...
GLC-2BX-D= Overview: Fiber Channel Transceiver for Enterprise Storage
The Cisco GLC-2BX-D= is a 2Gbps Fibre Channel SFP transceiver designed for high-speed storage area networks (SANs). Operating at 2.125 Gbps, it supports short-wavelength (850nm) multimode fiber (MMF) with a maximum reach of 500 meters on OM3/OM4 cables. Unlike generic SFPs, this module is Cisco MDS 9000-series certified, ensuring full compatibility with Fibre Channel switches like the MDS 9134T and MDS 9148S.
Key Technical Specifications
- Protocol Support: Fibre Channel (FC-PI-4), ANSI FC-PI-2, and SFP MSA compliant
- Connector Type: LC duplex
- Cable Compatibility: OM1 (62.5µm), OM2 (50µm), OM3/OM4 (laser-optimized)
- Power Consumption: 1.05W max, with DOM support for real-time temperature monitoring
Critical Use Cases
1. Legacy SAN Upgrades
The GLC-2BX-D= enables cost-effective upgrades for aging 1Gbps/2Gbps Fibre Channel SANs without requiring full infrastructure replacement. Its backward compatibility with 1Gbps FC switches like the Cisco MDS 9124 allows phased migrations.
2. Disaster Recovery Links
With 500m reach on OM4 fiber, it’s ideal for connecting primary data centers to secondary sites.
Addressing User Concerns
Q: Is GLC-2BX-D= compatible with non-Cisco switches?
While technically functional in third-party switches like Brocade, Cisco DCNM will flag uncertified hardware, causing management headaches. Firmware mismatch errors may also occur.
Q: Can it handle 4Gbps or 8Gbps Fibre Channel?
No. This transceiver is locked to 2.125Gbps FC speeds. For 4/8Gbps requirements, consider the Cisco DS-X6848-4G64 or DS-X6-F8-4G.
Deployment Best Practices
- Fiber Preparation: Use APC connectors to minimize back reflection in dense SAN environments.
- Firmware Updates: Always match the transceiver’s firmware to the Cisco NX-OS version on MDS switches to avoid CRC errors.
For enterprises prioritizing Cisco-validated hardware, the GLC-2BX-D= is available here, though stock availability depends on regional demand.
Common Troubleshooting Scenarios
1. Link Flapping on OM1 Fiber
This often stems from modal dispersion limits. Replace OM1 with OM3/OM4 cables or reduce link distance below 300m.
2. DOM Data Not Populating
Ensure switch firmware supports SFF-8472 standards. On older MDS 9134 switches, upgrade to NX-OS 6.2(25) or later.
Cost-Benefit Analysis: When to Choose This Transceiver
Having deployed these modules in banking SANs, the GLC-2BX-D= remains viable only for legacy FC-200/400 environments or low-budget archival storage. In hyperconverged infrastructures using NVMe-oF or 32G FC, its 2Gbps throughput becomes a bottleneck. However, for isolated backup networks or tape libraries still running FC-200, it provides a reliable, Cisco-supported path to avoid premature hardware retirement.