HPE 877691-B21 InfiniBand EDR/Ethernet 841QSFP28 2-Ports 100GbE PCI Express 3.0 x16 Network Adapter for ProLiant Server. Refurbished. In Stock Brand: HPE Part Number: 877691-B21 Condition: Refurbished Category: Transceiver Key Specs: 2-Port, 100GbE Availability: In Stock Shipping: Fast US-based shipping Order the HPE 877691-B21 today from ProDisk Network — your trusted source for enterprise IT hardware. All products are quality-tested and backed by our support team.
The 877691-B21 is a HPE transceiver component with interface PCI Express, network speed 100 GbE. Pro Disk Network sells the 877691-B21 for $305.26 with same-day US shipping and a 30-day return guarantee.
Reviewed By
Reviewed by:Pro Disk Network Engineering Team — . Specifications, compatibility, and pricing for the 877691-B21 are shown on this page.
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Same-Day US Shipping — orders before 3pm ET ship today via UPS
30-Day Returns — pre-paid label on DOA and defective items
Quick Answer: Is the 877691-B21 compatible with my switch?
Pro Disk Network validates every 877691-B21 against the target switch's published compatibility matrix before shipment. If you let us know your switch model and firmware version, we will confirm fitment and code the module appropriately (Cisco-coded, Juniper-coded, HPE-coded, etc.) at no extra charge.
How fast does the 877691-B21 ship?
Pro Disk Network dispatches the 877691-B21 same-day on orders confirmed before 3 pm ET. Multi-pallet projects requiring crating ship within 2 business days. International shipping (Canada, Mexico, EU, APAC) takes 3-7 business days via DHL Express or FedEx International Priority.
The 877691-B21 is deployed by US enterprises, MSPs, government, and education customers across multiple infrastructure scenarios. Below are the most common deployment patterns Pro Disk Network sees in real-world orders.
DCI (Data Center Interconnect) — Inter-DC routing or aggregation. LR4/LR8 transceivers for 10–80 km, ER4 for 40 km, ZR4 for coherent long-haul.
Campus Distribution — Catalyst-class campus distribution between IDF and MDF closets. PoE+ where wireless APs and IP phones share infrastructure.
Branch / Edge — Smaller form-factor switches and routers for branch sites. SD-WAN-compatible or static-VPN-attached as the architecture dictates.
What is the 877691-B21?
The 877691-B21 is a HPE network interface module with interface PCI Express and network speed 100 GbE, manufactured by HPE. Pro Disk Network ships this part new and certified-refurbished from our US warehouse with same-day dispatch on orders placed before 3 PM ET, backed by a 30-day return guarantee.
Pros & Cons of 877691-B21
Pros
Same-day US shipping cuts deployment downtime
Cons
Refurbished switches may show minor rack-rail wear
Power supplies sold separately on certain SKUs
Long-haul ZR4/CFP4 modules subject to export-control screening
Frequently Asked Questions about 877691-B21
Is the 877691-B21 a genuine HPE part?
Yes. Pro Disk Network sources every 877691-B21 as factory-original HPE inventory. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned HPE servers, surface-tested, and re-warranted by Pro Disk Network for 90 days.
Is the 877691-B21 compatible with my switch?
Pro Disk Network validates every 877691-B21 against the target switch's published compatibility matrix before shipment. If you let us know your switch model and firmware version, we will confirm fitment and code the module appropriately (Cisco-coded, Juniper-coded, HPE-coded, etc.) at no extra charge.
How fast does the 877691-B21 ship?
Pro Disk Network dispatches the 877691-B21 same-day on orders confirmed before 3 pm ET. Multi-pallet projects requiring crating ship within 2 business days. International shipping (Canada, Mexico, EU, APAC) takes 3-7 business days via DHL Express or FedEx International Priority.
What is the warranty on the 877691-B21?
New 877691-B21 units carry the full HPE manufacturer warranty (typically 1 to 5 years depending on product line). Refurbished and bulk-OEM units include a Pro Disk Network advance-replacement warranty (90 days refurbished). DOA replacement is free within 30 days of receipt.
Do you offer bulk pricing for the 877691-B21?
Email sales@prodisknetwork.com with the quantity and target ship date for a quote within one business day.
Optic Coding, Vendor Lock-In, and Multi-Vendor Compatibility
If you are running a multi-vendor leaf-spine architecture (Arista leaves and Cisco spines, for example), order optics coded for each endpoint separately. Optics in DAC and AOC cables are factory-coded to each end and cannot be flashed in-field. Plan the coding split at design time and document it in your network drawings.
Bandwidth Sizing for Spine-Leaf, EVPN-VXLAN, and Hyperconverged Storage
Sizing network bandwidth for a leaf-spine fabric using the 877691-B21 starts with the workload mix. For general-purpose virtualisation, plan 10G server-to-leaf, 25G or 40G leaf-to-spine; oversubscription up to 4:1 is acceptable. For hyperconverged storage (vSAN, Ceph, Storage Spaces Direct), plan 25G server-to-leaf at minimum, 100G leaf-to-spine, oversubscription 1.5:1 maximum. East-west traffic dominates in HCI clusters and starves on oversubscribed fabrics.