P21109-B21 is an HPE enterprise network adapter designed for high-performance connectivity in HPE ProLiant servers. It’s a dual-port 10/25 GbE SFP28 adapter based on the Intel X2522-Plus silicon, providing flexible high-speed networking for modern data center, virtualization, and storage workloads.
Why buyers pick P21109-B21 (plain English)
Flexible 10/25 GbE speeds Supports both 10 Gb and 25 Gb links so you can mix and match based on network infrastructure and performance needs.
Dual ports for redundancy and performance Two independent SFP28 ports allow link aggregation, path redundancy, or traffic segmentation without extra hardware.
Intel X2522-Plus performance Modern controller silicon with advanced offload and performance features — ideal for virtualized servers, storage clusters, and cloud-native workloads.
Enterprise-validated reliability Firmware and drivers are tested and supported by HPE for predictable behavior in ProLiant environments.
Compact and efficient SFP28 form factor keeps the card footprint small while delivering high bandwidth and efficient power usage.
60-second spec box (P21109-B21)
Adapter type Ethernet network adapter
Ports 2 × SFP28
Speed 10 GbE / 25 GbE
Controller Intel X2522-Plus
Form factor PCIe stand-up adapter
Host interface PCIe Gen4
Media supported SFP28 optics or DACs
Platform HPE ProLiant servers
Use case High-performance networking, virtualization, storage fabrics, scale-out clusters.
Where it fits (and when to choose something else)
Perfect for:
ProLiant servers needing dual 25 GbE links
High-bandwidth virtualized environments
Distributed storage and high throughput clusters
Path-redundant links and uplinks to 25GbE fabrics
Choose something else if:
You need higher aggregated speed → 100 GbE adapters
You want copper RJ-45 → 10/25 GbBASE-T NICs
You need lower speeds or legacy support → 10 GbE SFP+
TL;DR
P21109-B21 is HPE’s Intel X2522-Plus dual-port 10/25 GbE SFP28 adapter: a flexible, high-performance NIC for modern ProLiant servers requiring scalable 10/25 Gb networking with enterprise-grade support.
Key specifications
Feature
Specification
Device Type
Network Adapter / 25Gigabit Ethernet Card
Part Number
P21109-B21
Form Factor
Plug-in card / Stand-up
Interface (Bus) Type
PCI Express 3.0 x8
Ports
Dual SFP28 ports
Data Transfer Rate
Supports 10 Gigabit Ethernet and 25 Gigabit Ethernet, up to 25 Gbps
