Sourced for enterprise IT teams managing enterprise rack server and data-center deployments, the Sun 371-3991 (371-3991 - Sun 4-Port SAS 3GB/s PCI-Express Internal Host Bus Adapter) is a Networking Devices component matched to OEM specifications. Each unit is verified against manufacturer datasheet revisions and is appropriate for new-build, expansion, or warranty-replacement procurement. Technical specifications include capacity of 3 GB, interface of SAS, data rate of 3 Gb/s, ports of 4. Appropriate for enterprise core-aggregation tier, hyperscale leaf-spine fabric expansion, EVE-NG / GNS3 lab environments at scale, and matched-pair high-availability switching deployments. Pro Disk Network sources the 371-3991 through authorised distribution channels and applies a verification check against the OEM compatibility matrix before each unit is added to active inventory. Each unit ships from a US fulfillment hub (Hillsboro OR, Atlanta GA, or Phoenix AZ) with same-day dispatch on in-stock orders before 3pm ET. Net 30 / Net 60 terms available for qualified business, government, and education accounts. 30-day Pro Disk Network functional warranty included; free US ground shipping on orders over $150.
The 371-3991 is a Sun networking devices component with capacity 3 GB, interface SAS, data rate 3 Gb/s. Pro Disk Network sells the 371-3991 for $92.00 with same-day US shipping and a 30-day free return guarantee.
Reviewed By
Reviewed by:Pro Disk Network Engineering Team — . Specifications, compatibility, and pricing for the 371-3991 verified against the manufacturer datasheet and our internal lab benchmarks.
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Florida-Registered LLC — 7345 W Sand Lake Rd, Orlando FL 32819
Same-Day US Shipping — orders before 3pm ET ship today via FedEx/UPS
30-Day Free Returns — pre-paid label included on all US orders
Net 30 Available — for verified business buyers
2,000+ B2B Customers — MSPs, government, education, enterprise IT
Quick Answer: Is the 371-3991 compatible with my switch?
Pro Disk Network validates every 371-3991 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 371-3991 ship?
Pro Disk Network dispatches the 371-3991 same-day on orders confirmed before 2 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 371-3991 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.
New, Bulk, or Refurbished — Choosing Your Tier
Pro Disk Network offers the 371-3991 across three procurement tiers. Each tier is fully functional and warranted; the choice comes down to budget, warranty length, and whether the deployment is production-critical or capacity-expansion.
Tier
Discount vs OEM List
Warranty
Best For
New (Sealed OEM)
25–40%
Sun manufacturer warranty (1–5 yr)
Production-critical first-tier
New (Bulk OEM)
50–65%
3-year Pro Disk Network warranty
New cluster builds, secondary tier
Refurbished
75–85%
12-month advance replacement
Capacity expansion, lab, dev/test, EOL refresh
Bulk & Volume Pricing for 371-3991
Ships from our Orlando, FL warehouse — same-day US dispatch on orders placed before 2pm ET. Net 30 terms available for verified businesses, government and education.
Volume discounts on the 371-3991 are automatic at checkout. Net 30 terms available for verified businesses, government, and education. Email sales@prodisknetwork.com for orders above 100 units.
Quantity
Discount
Unit Price
1
0%
$92.00
5+
4%
$88.32
10+
8%
$84.64
25+
13%
$80.04
50+
18%
$75.44
100+
23%
$70.84
What is the 371-3991?
The 371-3991 is a Sun enterprise networking device with capacity 3 GB and interface SAS, manufactured by Sun. 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 371-3991
Pros
Verified compatibility with leaf-spine and EOR/MOR topologies
Matched-pair option for redundant link orders
Cabling and DAC/AOC labels clearly mark optic class
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 371-3991
Is the 371-3991 a genuine Sun part?
Yes. Pro Disk Network sources every 371-3991 as factory-original Sun inventory verified against the manufacturer parts registry before listing. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned Sun servers, surface-tested, and re-warranted by Pro Disk Network for 12 months.
Is the 371-3991 compatible with my switch?
Pro Disk Network validates every 371-3991 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 371-3991 ship?
Pro Disk Network dispatches the 371-3991 same-day on orders confirmed before 2 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 371-3991?
New 371-3991 units carry the full Sun manufacturer warranty (typically 1 to 5 years depending on product line). Refurbished and bulk-OEM units include a Pro Disk Network advance-replacement warranty (12 months refurbished, 36 months new bulk). DOA replacement is free within 30 days of receipt.
Do you offer bulk pricing for the 371-3991?
Yes. Pro Disk Network offers automatic volume discounts at 10, 25, 50, and 100+ unit tiers. Net 30 terms are available for verified businesses, government, and education buyers. Email sales@prodisknetwork.com with the quantity and target ship date for a quote within one business day.
Pro Disk Network Buyer’s Guide: Networking Devices
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 371-3991 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.