This Juniper QFX-QSFP-40G-ESR4 delivers Networking Devices functionality in a form factor and electrical specification matched to enterprise rack server and data-center deployments. The unit is built for 24/7 enterprise duty cycles and is verified against the OEM part-number registry before listing. Technical specifications include network speed of 40 GbE, wavelength of 850 nm, range of 300 m, features of QSFP. Workload fit covers VMware NSX overlay networking, Kubernetes pod-to-pod east-west bandwidth, Storage Replica replication, and high-throughput backup network paths between ToR switches and backup targets. Our procurement team maintains active inventory of the QFX-QSFP-40G-ESR4 and verifies condition, firmware revision, and OEM part-number registry alignment for each unit prior to sale. Stocked units ship same-day on in-stock orders placed before 3pm ET. Pro Disk Network applies a 30-day functional warranty and accepts Net 30 / Net 60 terms for qualified business accounts. Free US ground shipping on orders over $150; same-day expedited (UPS Next Day Air, FedEx Priority) available at checkout.
The QFX-QSFP-40G-ESR4 is a Juniper networking devices component with network speed 40 GbE, wavelength 850 nm, range 300 m. Pro Disk Network sells the QFX-QSFP-40G-ESR4 for $185.60 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 QFX-QSFP-40G-ESR4 verified against the manufacturer datasheet and our internal lab benchmarks.
Quick Answer: Is the QFX-QSFP-40G-ESR4 compatible with my switch?
Pro Disk Network validates every QFX-QSFP-40G-ESR4 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 QFX-QSFP-40G-ESR4 ship?
If in stock, the QFX-QSFP-40G-ESR4 ships same business day on US orders placed before 2 pm ET. Most US ZIP codes receive next-business-day or 2-day delivery via FedEx/UPS Ground or Express. Bulk and project orders shipping in pallets are typically dispatched within 24-48 hours.
The QFX-QSFP-40G-ESR4 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.
Spine-Leaf Fabric — Top-of-rack 25G/100G aggregation between leaf and spine switches. Match speed and form factor across both endpoints.
Server Uplink — 10G/25G server-to-leaf uplink — pair with matching DAC or AOC at the host NIC to avoid optic mismatch.
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.
New, Bulk, or Refurbished — Choosing Your Tier
Pro Disk Network offers the QFX-QSFP-40G-ESR4 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%
Juniper 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 QFX-QSFP-40G-ESR4
Ships from our US 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 QFX-QSFP-40G-ESR4 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%
$185.60
5+
4%
$178.18
10+
8%
$170.75
25+
13%
$161.47
50+
18%
$152.19
100+
23%
$142.91
What is the QFX-QSFP-40G-ESR4?
The QFX-QSFP-40G-ESR4 is a Juniper enterprise networking device with network speed 40 GbE and wavelength 850 nm, manufactured by Juniper. 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 QFX-QSFP-40G-ESR4
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
Not for hyperscale ZR coherent — different SKU family
Some vendors deprecate firmware on EOL part numbers
Mismatched optic+switch firmware can require manual override
Frequently Asked Questions about QFX-QSFP-40G-ESR4
Is the QFX-QSFP-40G-ESR4 a genuine Juniper part?
Yes. Pro Disk Network sources every QFX-QSFP-40G-ESR4 as factory-original Juniper inventory verified against the manufacturer parts registry before listing. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned Juniper servers, surface-tested, and re-warranted by Pro Disk Network for 12 months.
Is the QFX-QSFP-40G-ESR4 compatible with my switch?
Pro Disk Network validates every QFX-QSFP-40G-ESR4 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 QFX-QSFP-40G-ESR4 ship?
If in stock, the QFX-QSFP-40G-ESR4 ships same business day on US orders placed before 2 pm ET. Most US ZIP codes receive next-business-day or 2-day delivery via FedEx/UPS Ground or Express. Bulk and project orders shipping in pallets are typically dispatched within 24-48 hours.
What is the warranty on the QFX-QSFP-40G-ESR4?
New QFX-QSFP-40G-ESR4 units carry the full Juniper 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 QFX-QSFP-40G-ESR4?
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
Networking optics — SFP, SFP+, QSFP+, QSFP28 — are physically interoperable across vendors but logically restricted by firmware coding. The QFX-QSFP-40G-ESR4 is coded for a specific vendor family at our factory step before shipping, which preserves the OEM warranty workflow and allows the optic to be recognised without ‘service unsupported-transceiver’ CLI overrides. Mixing third-party optics with same-vendor optics in the same chassis is safe; mixing across vendor codings sometimes triggers warnings in the switch log.
Bandwidth Sizing for Spine-Leaf, EVPN-VXLAN, and Hyperconverged Storage
For EVPN-VXLAN overlays, the QFX-QSFP-40G-ESR4 carries the underlay tunnels in addition to the workload traffic. Plan for VXLAN encapsulation overhead (50 bytes) plus MTU headroom; set the underlay MTU to 9216 (jumbo frames) and the overlay MTU to 9000. Make sure both the QFX-QSFP-40G-ESR4 and the connected NICs support jumbo frames — some older NICs cap at 9000-byte payloads even when jumbo-enabled.