Nexus 9300 EX and FX Are End-of-Life — and the Official Replacement Is Not a 400G Box

Written and maintained by Haink's network infrastructure team · Milestones verified against Cisco bulletins, 22 August 2026 · authorized-channel, serial-verified

Two things usually get merged into one project here, and they should not be. Getting off end-of-life leaf switches is one decision. Moving the fabric to 400G is another. Cisco's named replacement for the EX and FX generations is the FX3 — a switch with 100G uplinks, exactly like the ones it replaces. If a data centre refresh is being justified on 400G, the FX3 is the wrong target and the budget conversation is a different one.

This page separates the two: what is actually end-of-life and when, what Cisco says replaces it, and what changes if the real goal is 400G.

What is end-of-life, and what is not

These are two very different tactical situations, and treating them as one "Nexus refresh" is the common planning error.

EX is urgent. No software maintenance since 2023, no security fixes since August 2025, and the last chance to hold a support contract expires this November. Anything running EX today is carrying unpatched infrastructure in the data centre core.

FX is not urgent. Software maintenance runs to July 2027 and security support to July 2029. You cannot put an uncovered FX switch onto a new contract — that closed in July 2025 — but a covered estate has three more years. FX is a planning item, not a fire.

FX2 has no end-of-life notice at all

Worth stating plainly, because it removes a whole line from many refresh proposals: as of August 2026 there is no end-of-sale or end-of-life bulletin for the FX2 generation — the 9336C-FX2, 93240YC-FX2, 93216TC-FX2, 93360YC-FX2 and the 9336C-FX2-E. We checked the full Nexus 9000 end-of-life listing; FX2 does not appear in it, and the product pages remain orderable.

So if the fleet is FX2, there is no lifecycle reason to move. A refresh there has to be justified on capacity or on 400G, not on a support deadline — and anyone presenting an FX2 replacement as EOL-driven should be asked which bulletin they mean.

What Cisco says replaces what

Both bulletins note that for a number of the older part numbers listed — bundles, accessories, some variants — "there is currently no replacement product available." Check the bulletin against your actual part numbers rather than against the family name.

The FX3 is a genuine one-for-one on ports and a real upgrade on features: MACsec on every port across the whole series, SyncE and PTP telecom profiles, GPS 1PPS/10MHz input and output on the 93180YC-FX3, and support for up to 162 FEX on the 93180YC-FX3 and 93108TC-FX3P. What it is not is a step to 400G.

If the goal is 400G, the target is GX or GX2

The uplinks on every FX3 model are 6×40/100G QSFP28. To get 400G in a Nexus 9300 you need a different platform:

Your existing optics carry over

This is the good news, and it changes the sequencing of a 400G project. Cisco's GX2 data sheet states that the QSFP-DD ports "also support native 200G (QSFP56), 100G (QSFP28), and 40G (QSFP+)" — the cage takes existing 100G and 40G modules directly and runs at the module's speed. There is no requirement to replace the transceiver estate to deploy 400G-capable hardware.

Combined with breakout, that produces the practical migration path: a 400G spine port breaks out to 4×100G down to the existing leaf switches, so the spine layer can be refreshed to 400G while the leaf layer stays exactly as it is. GX2 supports 4×10G, 4×25G, 4×50G, 4×100G and 2×200G breakout across its ports.

One constraint to design around: on the 93600CD-GX and the 9364C-GX, the 4×10G and 4×25G breakout modes are available on odd-numbered ports only, with the adjacent even port disabled. That halves usable density in those modes, and it needs to be in the port count from the start rather than discovered during staging. For any specific module-and-port combination, Cisco's TMG Matrix is the authority.

The software constraint: check the NX-OS minimum per part number

The FX3 family does not share one minimum release. The spread inside a single generation is wide enough to force an unplanned fabric upgrade:

The trap is that the two 93108TC-FX3 variants look almost identical on a quote. The FX3P — the one Cisco names as the replacement — will join a fabric running 9.3(x). The plain FX3 requires 10.4(2). Order the wrong suffix and the delivery triggers a fabric-wide software project.

In standalone NX-OS that is inconvenient. In ACI it is much worse, because switch image versions are tied to the APIC version. Adding a single new leaf whose minimum is 16.0(5) to a fabric running 15.1 means upgrading the APIC cluster and, in practice, the fabric. Sequence it deliberately: bring the APIC to a version that covers the most demanding part number you intend to buy, then introduce the new leaves.

Note also that the software trains this estate runs on are themselves being retired — Cisco has issued end-of-life notices for the NX-OS 9.3(x), 10.1(x) and 10.2(x) release families. An EX or FX switch frozen on 9.3 is frozen on a train that is itself closing.

Mode: FX3, GX and GX2 all run either way

There is no platform lock-in here. FX3, GX and GX2 all support both standalone NX-OS and ACI, so the hardware choice does not commit the fabric to one operating model. The real constraint is versioning, per the table above, not capability.

How to sequence a Nexus 9300 refresh

1. Separate the two projects. Getting off EX is a security and support problem with a November 2026 deadline. Moving to 400G is a capacity project with no deadline attached. They can share a purchase order but they should not share a justification.
2. Inventory by part number. EX, FX and FX2 are in completely different lifecycle positions, and FX2 is not end-of-life at all.
3. If replacing like for like, order FX3 — and check the exact suffix against the NX-OS minimum your fabric runs.
4. If 400G is the actual goal, price GX or GX2 at the spine and leave the leaf layer on 100G behind breakout. Existing QSFP28 optics carry into QSFP-DD cages.
5. In ACI, check the APIC version first. One leaf with a newer minimum pulls the whole fabric.
6. For EX specifically, decide before 7 November 2026 whether to renew coverage for the final ten months or to replace.

Frequently asked questions

Is the Nexus 9336C-FX2 end-of-life?

No. As of August 2026 there is no end-of-sale or end-of-life bulletin for the FX2 generation. The models remain orderable. Any FX2 replacement proposal has to be justified on capacity or 400G rather than on lifecycle.

What replaces the Nexus 93180YC-EX?

Cisco's bulletin names the N9K-C93180YC-FX3 — the same 48×1/10/25G plus 6×40/100G layout, with MACsec on all ports, SyncE and PTP telecom profiles added. The 93108TC-EX maps to the 93108TC-FX3P, which upgrades the copper ports to multigigabit and adds PoE.

Do I need new optics to move to 400G?

Not for the existing links. QSFP-DD ports accept QSFP28 100G and QSFP+ 40G modules natively and run at the module's speed, so a 400G-capable switch can be deployed against your current transceiver estate. New optics are needed only for links you actually want to run at 400G.

Can I upgrade the spine to 400G without touching the leaf switches?

Yes, and it is the usual path. A 400G QSFP-DD spine port breaks out to 4×100G toward existing leaf switches. Watch the breakout constraints on specific platforms — on the 93600CD-GX and 9364C-GX the 4×10G and 4×25G modes work on odd ports only, with the neighbouring port disabled.

What NX-OS version do I need for FX3?

It depends on the exact model: 9.3(5) for the 93108TC-FX3P, 9.3(7) for the 93180YC-FX3, but 10.4(2) for the plain 93108TC-FX3 and 10.4(1) for the 9348GC-FX3. Check per part number, not per family — the two 93108TC variants differ by three major releases.

How long can I keep running Nexus 9300 EX?

Support ends 31 August 2027, but security support already ended on 8 August 2025 — the switches receive no vulnerability fixes today. The last date to renew a service contract is 7 November 2026.

Related

• Cisco end-of-life guide — every family in migration, with the binding dates
• How to choose Cisco switches, routers and firewalls
• Leaf-spine networking — the architecture these switches build
• Cisco vs Juniper switching — Nexus versus QFX in the data centre
• Enterprise switches · Optic modules and transceivers · Cisco stock and lead times
• AI cluster architecture — where 400G leaf-spine actually earns its cost
• Telecom data hall — 400 kW, 12 racks, three-week turnkey deployment

Sources

• Cisco — 93180YC-EX and 93108TC-EX end-of-life bulletin
• Cisco — 93180YC-FX and 93108TC-FX end-of-life bulletin
• Cisco — full Nexus 9000 end-of-life notice listing (checked for FX2; no notice present)
• Cisco — Nexus 9300-FX3 data sheet (models, NX-OS and ACI minimums)
• Cisco — Nexus 9300-GX data sheet · Nexus 9300-GX2 data sheet (QSFP-DD backward compatibility, breakout modes)
• Cisco TMG Matrix — transceiver and platform compatibility