Juniper’s QFX5100 and QFX10002 series have been dependable data center workhorses — the QFX5100 as a 40GbE top-of-rack (ToR) switch and the QFX10002 as a modular 40G/100G platform. Both families are now in end-of-life (EOL) status, making this the right moment to plan a move to the modern 100GbE fixed platforms: the QFX5200-32C and the QFX5210-64C. This guide covers the four questions that matter to network, IT, and procurement teams: why upgrade, what to buy, what could go wrong in migration, and what it really costs.
Why Upgrade from the QFX5100 / QFX10002
Juniper has moved the QFX5100 and QFX10002 families through its end-of-life and end-of-sale process: new orders stop, feature development stops, and software and support eventually end. Exact dates vary by SKU, so check the EOL notices for your specific models — but the direction is the same: engineering investment has shifted to the fixed 100G QFX5000 family and beyond.
One practical consequence is software. The Junos releases available to QFX5100 and QFX10002 are frozen on older trains: fewer new features, a narrowing window of security and bug-fix releases, and eventually none. For a platform carrying network segmentation, automation, or EVPN-VXLAN fabrics, that is growing risk over time.
The hardware is also showing its age. The QFX5100-24Q-3AFO tops out at 24 ports of 40GbE; even the 32-port QFX5100-32Q offers only 40G density, while a modern ToR delivers 32 or 64 ports of 100GbE in the same 1U with 10G/25G breakout options. The modular QFX10002-36Q (36 x 40G) and QFX10002-72Q (72 x 40G) provide real 40G scale — the family also included the 60 x 100G QFX10002-60C — but in a power-hungry, multi-slot chassis that costs more to power and cool per usable port than a fixed 100G switch, with fabric and buffers sized for a previous generation of traffic.
Staying put carries hidden costs beyond the sticker price: maintenance renewals on EOL gear keep climbing as support windows tighten, spare parts become scarcer and more expensive, and every watt and rack unit spent on 40G gear is capacity you cannot spend on 100G workloads.
To be fair: if your data center runs low-bandwidth or non-critical workloads, a well-maintained QFX5100 or QFX10002 can keep serving for a while. The question is whether you plan the migration on your schedule — with tested hardware, a clean cutover, and a rollback path — or get forced into it later by an expired support contract.
What to Upgrade To: QFX5200 / QFX5210
The natural successors are the fixed-configuration 100G platforms: the 32-port QFX5200-32C and the 64-port QFX5210-64C. Both are available from LinkNewNet as tested pre-owned units in multiple airflow and power variants.
QFX5200-32C series. A 1U fixed switch with 32 x 100GbE QSFP28 ports and 3.2 Tbps of switching capacity, with support for 40G/25G/10G via QSFP28 optics, 40G QSFP+ optics, and breakout cables. It fits the classic ToR role — including replacing a QFX5100-24Q in the same rack footprint — and works as a compact spine for smaller fabrics. In-stock variants include QFX5200-32C-SAFO, QFX5200-32C-SAFI, plus LAFO, DCSAFO, and DCSAFI models for different airflow and AC/DC power requirements.
QFX5210-64C series. A 1U fixed switch with 64 x 100GbE QSFP28 ports and 6.4 Tbps of switching capacity — the high-density choice for spine aggregation or large leaf tiers. In-stock variants include QFX5210-64C-SAFO, QFX5210-64C-SAFI, plus DCSAFO, DCSAFI, and D-AFO2 models.
QFX5100 / QFX10002 vs. QFX5200 vs. QFX5210 at a Glance
| Capability | QFX5100-24Q (old ToR) | QFX10002-36Q / -72Q (old modular) | QFX5200-32C | QFX5210-64C |
|---|---|---|---|---|
| Port speed | 40GbE QSFP+ (10GbE via breakout) | 40GbE QSFP+ | 100GbE QSFP28 (40G/25G/10G options) | 100GbE QSFP28 (40G/25G/10G options) |
| Port density | 24 x 40G | 36 x 40G / 72 x 40G | 32 x 100G | 64 x 100G |
| Switching capacity | 960 Gbps | Depends on configuration | 3.2 Tbps | 6.4 Tbps |
| Form factor | 1U fixed | Modular chassis | 1U fixed | 1U fixed |
| Typical role | ToR | Modular ToR / spine | ToR / small spine | High-density spine / large leaf |
| Operating system | Junos OS | Junos OS | Junos OS / Junos EVO | Junos OS / Junos EVO |
| Lifecycle status | EOL | EOL | Current | Current |
Choosing the Right Model
The main decision between the two targets is density. Choose the QFX5200-32C when replacing a ToR or building a small-to-mid-size leaf-and-spine fabric where 32 x 100G per switch is enough. Choose the QFX5210-64C when you need 64 ports per switch — typically spine layers or large leaf tiers — or want to consolidate multiple 40G ToR switches into fewer 100G devices.
Is It a Drop-In Replacement?
At the rack level, yes: both new models are 1U fixed switches like the QFX5100-24Q, so footprint is not the blocker — airflow and power are. Juniper’s AFO (front-to-back) and AFI (back-to-front) airflow variants must match your cold-aisle direction, and AC vs. DC power variants must match your rack power.
On the optics side, existing 40G QSFP+ optics and DACs can often be reused in QSFP28 ports at 40G speeds — check Juniper’s supported-optics matrix for your exact part numbers. To actually get 100G, you will need new QSFP28 optics or DACs. This makes the QFX5200-32C a natural same-rack upgrade: keep 40G links running on day one, then move to 100G as uplinks and optics are refreshed.
Migration: What to Watch For
Junos configuration does not copy-paste unchanged. Interface naming stays in the et-* family, but breakout ports use subport syntax such as et-0/0/0/0, and aggregation, MC-LAG, and EVPN-VXLAN statements differ between old and new platforms. Rebuild the configuration from a current backup rather than assuming parity — especially for VLAN/VNI mapping, ESI/LAG, and route targets. If you run Junos EVO on the new switches (available alongside classic Junos on current releases), budget extra time: EVO’s management architecture differs, and not every legacy CLI statement maps one-to-one.
- Optic and DAC compatibility. The most common day-of-cutover surprise. Validate every transceiver, DAC, and breakout cable against the Juniper supported-optics table for the target model and Junos release before the maintenance window.
- Airflow direction. Installing the wrong AFO/AFI variant relative to your cold aisle causes thermal alarms and shortened hardware life. Order the matching orientation upfront.
- Power budget. Confirm rack PDU capacity and circuit sizing for the new power supplies — exact draw depends on configuration.
- Licensing and support. QFX5200 and QFX5210 are licensed under Juniper’s subscription-based Junos software model. Existing QFX5100/QFX10002 perpetual entitlements do not automatically transfer — confirm licenses and support are active before go-live.
- Breakout differences. Re-verify breakout mapping between 40G (4 x 10G) and 100G (4 x 25G or 4 x 10G) subports; the subport numbering changes with port speed.
- EVPN-VXLAN. Re-validate VLAN/VNI mapping, ESI/LAG, route targets, and VTEP addresses — syntax and defaults differ across platforms and Junos trains.
- Routing, QoS, and ACLs. Confirm policies produce the same behavior on the new hardware pipeline; some hardware-specific profiles need rebuilding rather than pasting.
Cutover and rollback. Treat the move like a maintenance window, not a swap. Stage the new switch in parallel, load the target Junos release, apply and test the configuration off-line, and keep a full backup of the old configuration plus a documented rollback path. Migrate one leaf or one fabric segment at a time so you can validate and reverse quickly.
Post-cutover verification checklist: all interfaces up at expected speeds, transceiver inventory and optics status, LAG/MC-LAG members and peer consistency, EVPN-VXLAN VTEP and VNI state, routing adjacencies, MTU end-to-end, management reachability and monitoring restored — then run a real traffic test before closing the window.
Cost & Buying Options
Three realistic paths exist, and their economics differ. Buying new gives you full warranty and the freshest software, but at list price and with lead times that can stretch. Extending maintenance on QFX5100/QFX10002 is the cheapest in the short term, but you are paying to keep EOL gear alive — no new features, rising renewal costs, and harder-to-find spares. Tested pre-owned 100G platforms from LinkNewNet sit in the middle: current-generation hardware at a fraction of list price, tested before shipping, and typically available from stock.
Look beyond purchase price. The QFX5200-32C and QFX5210-64C deliver 100G with significantly better power-per-port than the QFX10002 modular chassis, in fewer rack units, with modern buffer and fabric design for leaf-spine and EVPN-VXLAN fabrics. Over a three-to-five-year horizon, those savings can outweigh the upfront difference — which makes tested used hardware even more attractive.
LinkNewNet specializes in tested pre-owned Juniper data center gear. Units are inspected, functionally tested, and shipped with warranty options, and because we stock multiple airflow and power variants — QFX5200-32C SAFO/SAFI/LAFO/DCSAFO/DCSAFI and QFX5210-64C SAFO/SAFI/DCSAFO/DCSAFI/D-AFO2 — you can match your rack without a build-to-order wait. Pricing is configuration-specific, so send us your current model, airflow direction, and optics inventory for a validated quote.
Plan Your Upgrade
The upgrade from QFX5100 / QFX10002 to QFX5200 / QFX5210 is straightforward if you plan it: pick the right density, match airflow and power, re-apply your Junos configuration, verify optics and licenses, and keep a rollback path. LinkNewNet can supply tested pre-owned QFX5200-32C and QFX5210-64C units in the variants your racks need, with testing and warranty support to de-risk the migration. Contact LinkNewNet with your current model, port counts, and optics list — we will help you map the migration and quote validated hardware.
