Key Technical Specifications
| Parameter | Specification |
|---|---|
| Module Model | A2H254-16 / P0973BK |
| Port Configuration | 16 × 10/100Base-TX RJ-45 |
| Switching Layer | Layer 2 (MAC address-based forwarding) |
| Chassis Compatibility | Enterasys I/A Series modular switch chassis |
| Hot-Swap Support | Yes (module-level replacement) |
| VLAN Support | IEEE 802.1Q VLAN |
| QoS | Priority queuing / traffic classification |
| Security Features | ACL, port security, MAC address filtering |
| Management | CLI, Web GUI, SNMP |
| Power | Supplied by chassis backplane (module-specific wattage per OEM datasheet) |
| Operating Temperature | Approximately -20°C to +60°C (verify with OEM datasheet) |
| Dimensions | Module form factor; approx. 48 mm × 148 mm × 228 mm (verify with OEM datasheet) |
Product Introduction
Plant-floor networks don’t forgive sloppy hardware. When a 16-port access module dies on an old Enterasys I/A Series chassis, you’re not just losing ports — you’re losing visibility into whatever PLCs, HMIs, or instrumentation are hanging off those drops. The Enterasys A2H254-16 P0973BK is the 16-port 10/100Base-TX line card that slots into the I/A Series modular chassis and handles Layer 2 MAC forwarding, VLAN segmentation, QoS prioritization, and basic ACL security. It’s not glamorous. It just works.The reason engineers still hunt for this card is simple: it’s a direct drop-in for an existing I/A Series rack. No rewiring. No new chassis. No re-architecting the network. You pull the dead module, slide this one in, and the chassis firmware handles the rest. One caveat — Enterasys was acquired by Extreme Networks years ago, and firmware support varies by chassis OS version. Always confirm your chassis firmware can recognize the A2H254-16 before you crack the box.
Quality SOP & Tech Pitfalls
The Lab Report (Pre-Shipment Protocol)
- Visual & counterfeit check — Inspect the P0973BK label, serial number, PCB revision, RJ-45 port condition, and edge connector pins. Reject anything with corrosion, bent pins, or mismatched labels.
- Chassis live test — Seat the module in a compatible Enterasys I/A Series chassis. Confirm the chassis recognizes the module, port LEDs illuminate, and no fault indicators are active.
- Port-level verification — Patch a known-good device into several ports. Verify link negotiation at 10/100 Mbps and basic frame forwarding.
- Firmware & revision logging — Record the chassis firmware version and module hardware revision. This matters for compatibility.
- Anti-static sealing — ESD strap on, module in a static bag with desiccant, photographed before boxing.
The Engineer’s Warning (Pitfalls That Cause Downtime)
- Chassis compatibility is not universal. The A2H254-16 only works in specific Enterasys I/A Series chassis. It will not fit a standalone fixed-port switch. I’ve seen someone order three of these for a non-modular chassis — wasted a week and a budget line.
- Firmware mismatch kills recognition. Even in the right chassis, an outdated chassis OS may not properly initialize the module. Check the release notes for your chassis firmware before swapping.
- Don’t assume “P0973BK” is just a cosmetic code. The P0973BK suffix can denote a specific hardware revision or regional variant. Cross-reference it against your existing module label.
Installation & Configuration Guide
1. Pre-Installation (⚠️ Critical)
- Notify your network team. Even though the module is hot-swappable, pulling a live card drops all 16 ports simultaneously.
- Photograph the existing module: model label (A2H254-16 / P0973BK), slot number, and port-to-device mapping.
- Back up the current chassis configuration via CLI or SNMP management.
2. Removal
- If possible, administratively disable the ports on the old module to prevent MAC table flapping.
- Release the module ejector levers or retention screws.
- Slide the module straight out. Place it in an ESD bag immediately.
3. Installation
- Verify the slot. Ensure the target slot supports 10/100 Ethernet modules (some slots may be reserved for uplink or management cards).
- Align the module with the slot guides and seat it firmly until the backplane connector engages. Lock the retainers.
- Reconnect patch cables to the correct ports using your port map.
4. Power-On & Testing
- Confirm the chassis recognizes the module (check CLI
show moduleor equivalent command). - Verify port LEDs: link lights should illuminate when devices are connected.
- Test connectivity on several ports. Confirm VLAN assignments and QoS policies are inherited from the chassis configuration.
- Monitor the MAC address table for 10–15 minutes to ensure stable learning and no flapping.
Compatible Replacement Models
| Compatibility Tier | Model | Notes |
|---|---|---|
| ✅ Drop-in Replacement | A2H254-16 P0973BK (same revision) | Exact match. Verify hardware revision and chassis firmware. |
| ⚠️ Software Compatible | A2H254-16 (alternate P-code revision) | Same 16-port 10/100 function. May require chassis firmware update. Verify P-code suffix. |
| ⚠️ Software Compatible | A4H254-8F8T (P0973JP) | 8× fiber + 8× copper combo module for I/A Series. Different port mix — requires config adjustment. |
| ❌ Hardware Mod Required | Non-I/A Series Enterasys/Extreme fixed switch | Different form factor entirely. Requires full network redesign. |
Frequently Asked Questions (FAQ)
Can I hot-swap this module without taking down the whole chassis?
Yes — the I/A Series chassis supports hot-swappable line cards. But all 16 ports on that module will drop during the swap. Plan a maintenance window and notify affected users.Will this work in any Enterasys chassis?
No. It only fits I/A Series modular chassis. Check your chassis model and slot compatibility before ordering. A fixed-port Enterasys switch won’t accept this card.Is P0973BK the same as A2H254-16?
A2H254-16 is the module model number. P0973BK is the associated part/order number. They refer to the same 16-port 10/100 module, but always verify the full label against your existing card.What if my chassis firmware is old?
Update the chassis firmware first if possible. An outdated OS may not properly initialize newer hardware revisions of the A2H254-16. Check the Extreme Networks/Enterasys release notes for your chassis model.Can I use this in an industrial environment?
The operating temperature range is approximately -20°C to +60°C per available data. That covers most indoor industrial cabinets, but it’s not a hardened DIN-rail switch. If you’re mounting it in a hot control room or an unconditioned enclosure, verify ambient temps first.Does this come with a warranty?
Surplus and refurbished units typically carry a 12-month defect warranty from reputable suppliers. Confirm warranty terms in writing before purchasing.What happens if the module isn’t recognized after installation?
Reseat the module first. Then check the chassis CLI for module status. If it still isn’t recognized, verify the chassis firmware supports this hardware revision and confirm the slot is compatible with 10/100 Ethernet modules.
