817749-B21 - HPE Ethernet 10/25Gb 2-port 640FLR-SFP28 Adapter

HPE 817749-B21 — Ethernet 10/25Gb 2-Port 640FLR-SFP28 Adapter

What it is

817749-B21 is an HPE enterprise Ethernet network adapter designed for HPE ProLiant servers.
It’s a dual-port 10/25Gb SFP28 FlexibleLOM (FLR) adapter that provides high-bandwidth, low-latency network connectivity for modern data center and cloud workloads.

Why buyers pick 817749-B21 (plain English)

High-speed server networking
Supports both 10GbE and 25GbE, allowing flexible migration to higher bandwidth without replacing hardware.

FlexibleLOM form factor
Installs in the dedicated FLR slot, preserving PCIe slots for storage or accelerators.

Dual-port redundancy
Two SFP28 ports support link aggregation, failover, or network segmentation.

Enterprise-ready features
Optimized for virtualization, container platforms, and software-defined networking.

ProLiant-validated
Firmware and drivers are qualified for HPE servers to ensure stability and support.

60-second spec box (817749-B21)

Adapter type
Ethernet network adapter

Ports
2 × SFP28

Speed
10GbE / 25GbE

Form factor
FlexibleLOM (FLR)

Host interface
PCIe (via FLR slot)

Supported media
SFP28 DACs or optical transceivers

Platform
HPE ProLiant servers with FLR support

Use case
High-bandwidth server networking, virtualization, cloud, and storage traffic.

Where it fits (and when to choose something else)

Perfect for:

• ProLiant servers with FlexibleLOM slots

• Virtualized and cloud workloads

• Storage traffic (iSCSI, NFS, vSAN)

• 10Gb to 25Gb network upgrades

Choose something else if:

• You need more than two ports → choose quad-port adapters

• You need copper Ethernet → choose RJ-45 adapters

• You need 40Gb/100Gb speeds → choose higher-speed NICs

TL;DR

817749-B21 is HPE’s dual-port 10/25Gb FLR Ethernet adapter with SFP28 interfaces:
a flexible, high-performance networking solution for ProLiant servers that preserves PCIe expansion slots