Description
Enterasys A4H254-8F8T | SecureStack Switch, New Surplus
Architect’s Product Breakdown
The Enterasys A4H254-8F8T is a versatile, secure managed switch designed explicitly to bridge traditional copper Ethernet devices with long-distance, noise-immune optical links. Featuring a hybrid port layout—combining eight Fast Ethernet fiber ports and eight copper ports alongside dedicated gigabit uplinks—it is frequently deployed in harsh industrial automation environments, power generation plants, and distributed SCADA network edges where electromagnetic interference (EMI) threatens standard cabling.
The unit supports Enterasys SecureStack architecture, allowing up to eight switches to be linked and managed as a single logical entity. It incorporates enterprise-grade management, robust QoS prioritization for real-time traffic (such as VoIP or industrial automation control packets), and comprehensive security frameworks like IEEE 802.1X authentication.
A4H254-8F8T
Key Technical Specifications
| Parameter | Specification |
| Manufacturer | Enterasys (Extreme Networks) |
| Model / Part Number | A4H254-8F8T |
| Product Family | SecureStack A4 Series |
| Fiber Ports | 8 × 100BASE-FX (Multimode, MT-RJ connectors) |
| Copper Ports | 8 × 10/100BASE-TX (RJ-45) |
| Uplink / Stacking Ports | 2 × 10/100/1000 Mbps RJ-45 & 2 × 1000Base-X SFP slots |
| Switching Capacity | 11.2 Gbps (Switch) / 89.6 Gbps (Stack) |
| Management Interfaces | CLI, SNMP, RMON, WebView Web Interface |
| Power Requirements | 100 – 240 VAC (47.1 W Max Consumption) |
| Operating Temperature | 0°C to +50°C (32°F to 122°F) |
Field Engineer’s Pitfall Guide (Unique Value)
- MT-RJ Fiber Cleanliness: The optical fiber ports utilize MT-RJ connectors, which are exceptionally sensitive to dust and oil contamination. Always inspect and clean optical patch leads with approved wipes prior to insertion to prevent packet loss or link down states.
- Stack Firmware Version Alignment: When hot-adding or swapping an A4H254-8F8T into an existing active SecureStack ring, verify that the running firmware versions match exactly to prevent stack initialization stalls or split-brain network topologies.
- Mixed Media Grounding Practices: Ensure that the switch chassis is solidly tied to the panel ground bus. Mixing unshielded copper drops with high-voltage industrial perimeters can introduce common-mode transients if proper earth bonding is omitted.
QA & Testing SOP (Transparency)
- Visual & Origin Verification: Units are inspected for authentic OEM labeling, clean chassis housing integrity, and unobstructed optical/copper port pins.
- Port-by-Port Traffic Loopback: Every hybrid port (both copper RJ-45 and fiber MT-RJ/SFP interfaces) undergoes rigorous line-speed packet transmission and error-rate testing using automated test gear.
- Management & Core Function Checks: Units are booted on a test bench to validate flash memory integrity, CLI responsiveness, web management access, and factory default restoration.
- Anti-Static & Secure Packaging: Post-testing, units are wrapped in static-dissipative materials and packed in heavy-duty, foam-lined corrugated boxes to safeguard delicate optical transceivers during transit.
Technical FAQ
- Can this switch operate as a standalone unit? Yes. While it supports Enterasys SecureStack multi-unit architecture, it functions fully as an independent managed switch.
- What type of fiber cable is required for the optical ports? The onboard 100FX ports use MT-RJ connectors designed for standard multi-mode fiber optic cabling.
- Is this switch compatible with legacy DCS networks? Yes. Due to its high reliability and fiber isolation capabilities, variants of this switch are frequently utilized as drop switches in Foxboro Invensys and similar industrial control architectures.
- What warranty is provided with a surplus unit? Units carry a standard 12-month replacement warranty backed by comprehensive bench testing and verification.
