Cisco Meraki MS420-48 EoL: Migrate to the MS425-32

If a Cisco Meraki MS420-48 (PID MS420-48-HW) is still anchoring an aggregation layer or collapsed core anywhere in your network, it is now past every Cisco lifecycle milestone that matters. The MS420-48 reached its Last Day of Support on October 31, 2023. From that date forward Cisco provides no firmware updates, no PSIRT security fixes, and no TAC or RMA hardware replacement for this model. The switch still forwards packets at line rate, which is exactly why these units quietly persist in production long after they should have been retired. This guide explains what the end-of-life dates actually mean for a switch sitting in the data path, why the recommended Meraki MS425-32 is the right successor for this specific switch class, and how to plan a clean cutover that does not strand your distribution or access layer.

What the MS420-48 actually was

The MS420-48 was Meraki's high-density Layer 3 aggregation switch: 48 ports of 10 Gigabit SFP+, fully cloud-managed through the Meraki dashboard, with hardware Layer 3 routing (static routes, OSPF, ACLs, DHCP relay, and warm-spare gateway redundancy). It was a fiber-first box — every port is SFP+, so it took 10G fiber and DAC links from distribution switches, hypervisor hosts, and storage, with no built-in copper or multigigabit access ports. Power was modular with field-replaceable supplies and fans, and it provided non-blocking switching across its 48 ports. In 2014–2016 it was a sensible way to collapse a 10G aggregation tier under single-pane cloud management instead of a CLI-driven chassis. What it never had, by design, were 40G/100G uplinks or physical stacking — every uplink was just another 10G SFP+ port, and resiliency was built from warm-spare pairs rather than a stacked virtual chassis.

Why acting now matters

The dangerous part of an end-of-life aggregation switch is not that it stops working. It is that it keeps forwarding traffic while the support floor disappears beneath it — and an aggregation switch sits in the path of everything below it, so its blast radius is the whole closet or pod. Three concrete exposures stack up after LDoS:

• No PSIRT security fixes. When a new vulnerability is disclosed in the switching firmware, dashboard agent, or a protocol stack the MS420-48 runs, it will not receive a fixed image. Its firmware is frozen at the end-of-support cutoff, so any applicable CVE on that code is permanent and unpatchable.
• No TAC or RMA. A failed MS420-48 cannot be opened as a support case or swapped under contract. Your only recovery is a spare you bought before LDoS or a gray-market unit of the same dead-end model — and a hard failure at the aggregation layer takes everything downstream of it with it.
• Audit and compliance exposure. The frameworks that federal, DoD, SLED, and healthcare buyers operate under — FedRAMP, CMMC, the HIPAA Security Rule, PCI DSS, and CISA directives — assume supported, patchable infrastructure. NIST 800-53 SI-2 (flaw remediation) and its equivalents presume the vendor still ships fixes. An unsupported core/aggregation switch that cannot be patched is a finding waiting to happen, and 'the vendor no longer issues updates' is not a defensible remediation plan for an Authority to Operate or a PCI attestation.

There is also a dashboard trap unique to cloud-managed Meraki gear. Past LDoS, an EoL switch can lose the ability to claim a current license SKU, can be excluded from new firmware trains your other switches are moving to, and can eventually fall out of dashboard manageability entirely. As you modernize the rest of the network the MS420-48 becomes the one device holding the whole org back on an old firmware baseline.

What each milestone means in practice

• End of Sale (2016-10-31): the last day Cisco/Meraki accepted new orders for the MS420-48. Everything after this date has been running on the support tail.
• End of Software Maintenance: Meraki does not publish a separate per-model maintenance-release date the way IOS-XE platforms do, because firmware is pushed centrally from the cloud. In practice, maintenance for this hardware was wound down on the path to LDoS.
• Last Day of Support / LDoS (2023-10-31): the hard wall. No TAC, no RMA, no firmware or security fixes, and no guaranteed dashboard support. The hardware is on its own from this date.

The recommended replacement: Meraki MS425-32

Cisco's migration guidance routes the MS420 line to the MS425 aggregation family — the MS425-16 for smaller aggregation needs and the MS425-32 (PID MS425-32-HW) as the direct successor to the 48-port MS420-48. The MS425-32 keeps the model you already operate (cloud-managed, Layer 3, fiber SFP+ aggregation) and modernizes the parts that matter for a switch in this role:

• 32 x 10G SFP+ plus real 40G uplinks. Rather than burning 10G ports for uplinks, the MS425-32 provides dedicated 40G QSFP+ uplink ports. You aggregate distribution/access at 10G and connect northbound to the core at 40G — a four-fold uplink jump the all-10G MS420-48 simply could not provide.
• Physical stacking over 40G. The MS425 uses its 40G QSFP+ ports for high-bandwidth physical stacking, so two units form a resilient, single-managed logical aggregation pair with cross-stack link aggregation. The MS420-48 had no physical stack at all; it relied on warm-spare pairing only. This is the single biggest architectural upgrade for an aggregation tier.
• Carrier-class redundancy. The MS425-32 ships with dual hot-swappable, load-sharing power supplies and redundant hot-swappable fan trays, so a PSU or fan failure does not drop the aggregation switch — a meaningful step up for a device the whole pod depends on.
• Same operating model, longer runway. It is managed in the same Meraki dashboard, supports the same Layer 3 feature set (OSPF, static routing, ACLs, DHCP, warm spare/VRRP-style gateway redundancy), and lands you on current, supported, actively-patched firmware with years of support ahead instead of a frozen baseline.

Licensing: per-switch Meraki, plan the term

Meraki licensing is subscription-based and tied to the device for the life of the license. The MS425 is licensed per switch under the Meraki MS license model (Enterprise or, where you want the richer routing and analytics feature set, Advanced), co-terminated against your existing dashboard organization. Budget for the subscription term, not just the hardware, and decide up front whether you co-terminate the new MS425 licenses to your existing org expiry date or start fresh. Confirm your Meraki dashboard organization and license entitlement are provisioned before the switch arrives so it claims and comes online cleanly — this is the most common thing teams forget on a Meraki refresh.

A practical migration plan

1. Assessment and inventory

Pull an exact count of MS420-48-HW units and their role (aggregation, collapsed core, or distribution). For each, export from the dashboard the full port map: which SFP+ ports are in use, the optics/DAC type per port (10GBASE-SR/LR, SFP+ DAC), VLAN and trunk configuration, Layer 3 interfaces and routes (OSPF areas, static routes, SVIs/gateway IPs), ACLs, DHCP relay, and any warm-spare pairing. Capture the physical layer too: rack location, redundant power feeds, and the fiber plant feeding each port.

2. License and dashboard transition

Claim the new MS425-32 (or stacked pair) into the same dashboard organization and network. Reconcile licensing — co-terminate or renew — so the new switch is fully entitled before cutover. Because both old and new switches live in one dashboard, you can stage the MS425 configuration alongside the live MS420-48 without touching production.

3. Config and feature parity

Recreate VLANs, trunks, Layer 3 interfaces, OSPF/static routing, ACLs, DHCP relay, and QoS on the MS425 from the inventory you exported. Confirm parity on every Layer 3 feature the MS420-48 was carrying — gateway/warm-spare IPs especially, since the aggregation switch is often the default gateway for downstream subnets. Decide your resiliency model now: if you are moving from a warm-spare MS420 pair, the MS425 stack gives you a stronger single-logical-switch option, but cabling and gateway design change accordingly.

4. Physical, optics, and stacking

Inventory optics carefully — the MS420-48 is all SFP+, and most 10G SFP+ optics and DACs carry straight over to the MS425's SFP+ ports, but verify compatibility and quantities. The new piece is the 40G layer: budget QSFP+ optics or 40G stacking/DAC cables for the MS425 uplinks and stack links, which did not exist on the MS420-48. Plan rack space for redundant PSUs and ensure both power feeds are available. If you are stacking a pair, cable the 40G stack links before bringing the access ports live.

5. Phased cutover

Stage the MS425 fully configured and uplinked in parallel with the live MS420-48. Cut over during a maintenance window by moving downstream links and the northbound uplink in a planned sequence — typically uplink first to verify Layer 3 reachability and routing convergence, then access/distribution links in batches with verification between each. Keep the MS420-48 physically in place and powered (but offloaded) until you have soaked the new switch through a full business cycle, so rollback is a cable move rather than a re-rack.

6. Secure decommission

A decommissioned MS420-48 still holds configuration, routing details, and dashboard association. Remove it from the dashboard organization and your asset/NMS records, factory-reset the hardware, and for federal and healthcare environments follow your media-sanitization and asset-disposal policy (NIST SP 800-88 style handling) with documented chain of custody before the unit leaves the building.

Procurement notes for government and enterprise buyers

Source the MS425-32 and its optics through an authorized Cisco/Meraki partner. For US federal, DoD, and SLED buyers, confirm TAA compliance and country-of-origin documentation up front, validate that units carry genuine Meraki serials with clean license entitlement, and plan for current lead times on aggregation switches and 40G optics rather than assuming stock. Government Purchase Card (GPC) orders, contract vehicles, and quote-to-PO timelines all benefit from engaging the partner early so licensing, TAA paperwork, optics, and delivery line up with your fiscal calendar. Buying gray-market or used MS420-48 units to extend a dead platform only deepens the audit and support problem.

Ready to scope the swap? Review the full milestone detail for this model on the MS420-48-HW EoL page, browse current aggregation switches in our catalog, and see the broader migration picture on the Cisco EoL hub. When you are ready, get a refresh quote and we will size the MS425-16 or MS425-32 — single or stacked — along with licensing, optics, and 40G uplinks to match your existing MS420-48 footprint.