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Meraki MS410 hardware overview

The Meraki MS410 series switches (codename “Wolfcastle”) offer 16 or 32 1000Mbit SFP ports, 10G SFP+ uplink ports, two HiGig2 (QSFP+) stacking ports, and a Gigabit Ethernet management port.

Meraki MS410-16 internal view

Meraki MS410-16 internal view

The MS410 was discontinued in September 2024, and is too old to support secure boot.

Here is a quick summary of the MS410-16 specs:

  • Broadcom BCM56548 (A0) ASIC
  • Broadcom BCM54285C1KFBG QSGMII Octal Gigabit PHY
  • Broadcom BCM82752A3KFSBG PHY
  • 16MB of SPI flash (MX25L12805D)
  • 1GB DDR3 RAM (SK Hynix H5TC4G63EFR; soldered, ECC, PDF datasheet)
  • 1024MB NAND flash (Micron MT29F8G08ABACAWP; PDF datasheet)
  • MA-PWR-250WAC (identical to PWR-C2-250WAC)

The UART header in the MS410-16 is J2 and follows the standard Meraki UART pinout (1: 3.3V Vcc, 2: Tx, 3: Rx, 4: GND) at 115200 baud.

Broadcom BCM56548A0KFSBLG

Unlike the MS420-24 and MS425-16, the MS410-16 is not a cut-down version of the MS410-32 with fewer PHYs and SFP cages. As the BCM56548 supports only 24 ports, we can speculate that the MS410-32 may use two stacked internally.

The MS410 is quite rare on the used market, and I am not aware of any MS410-32 available for a reasonable price. If you have one and are interested in donating it, claimed status does not matter, please reach out!


Unlike the MS350, MS420, and MS425, the management plane in the MS410 is not a discrete CPU but is integrated into the StrataXGS ASIC, similar to the MS210/225/250 series. The MS410 runs the same firmware release (switch-arm) as the MS210/MS225/MS250 series.

As the CPU is integrated into the switch ASIC, there are no devices present on the PCI(e) bus.

The Broadcom SDK series implements the packet engine in userspace, using the GPL-licensed linux_kernel_bde and linux_user_bde kernel modules to interface with the ASIC. In the Meraki firmware, the packet engine is a component of the userspace click daemon, which loads the bcm_click shared object during click router initialisation.


The stock Meraki boot process uses U-Boot on SPI to load a “bootkernel” (also from SPI), which then initializes NAND and using kexec boots the main firmware. The firmware layout follows the standard Meraki practice of having A/B firmware images: bootkernel1, bootkernel2, part.safe, part.old.

The firmware layout on SPI is:

0x000000-0x100000 : "uboot"
0x100000-0x800000 : "bootkernel1"
0x800000-0xf00000 : "bootkernel2"

The MS410 design predates Cisco Aikido secure boot, and therefore the firmware is not signed. Unlike recent Meraki products, U-Boot on the MS410 is not compiled with ENV_IS_NOWHERE, as we can see from the bad CRC, using default environment line below:

Press Ctrl-C to run Shmoo ..... skipped
Restoring Shmoo parameters from flash ..... done
Running simple memory test ..... OK
DeepSleep wakeup: ddr init bypassed 3
Enabling DDR ECC reporting
clear_ddr: OK
Enabling DDR ECC correction
DDR Interface Ready
DRAM:  1 GiB
WARNING: Caches not enabled
NAND:   Micron MT29F8G08ABACA, blocks per lun: 1000 lun count: 1
256 KiB blocks, 4 KiB pages, 27B OOB, 8-bit
NAND:   chipsize 1024 MiB
SF: Detected MX25L12805D with page size 64 KiB, total 16 MiB
*** Warning - bad CRC, using default environment

By default no U-Boot environment is present on SPI NOR, so U-Boot uses the environment compiled into the binary, which has bootdelay=0 and thus you cannot interrupt the automatic boot.

However, if you create a valid environment at 0xc0000 with a positive bootdelay, then you can interrupt U-Boot and obtain a shell. 0xc0000 is the default offset for storing the U-Boot environment on this generation of Broadcom switching ASICs, which Meraki has not modified.

Ghidra disassembly of U-Boot binary showing environment read offset; Meraki have not provided the U-Boot source code for the MS410.

Networking is functional in U-Boot, so it is possible to boot arbitrary payloads via tftpboot.


Similar to the MS250, the two 40mm system fans in the MS410 are controlled by an onsemi adt7475 (PDF datasheet). The MS410 fans have a Meraki part number: MA-FAN-16K (P/N 680-36010) and contain the Delta FFB0412UHN-C (PDF datasheet). These are identical to the Cisco FAN-T1, which can be purchased for considerably less than the Meraki branded part.

The MS410 accepts two hot-swap power supplies (model MA-PWR-250WAC, P/N 640-20010), which in my units are Delta model DPS-250AB-86 with 12V/20.83A output. Note that the MA-PWR-250WAC is physically and electrically compatible with PWR-C2-250WAC. Higher wattage power supplies like the PWR-C2-640WAC and PWR-C2-1025WAC will also power the MS410.

Idle power consumption:
MS410-16: 35W
MS410-32: Unknown

Meraki have chosen to EoL all of their Broadcom based switches. Being a Broadcom design, the MS410 was axed from the product portfolio on 2024-09-28. The MS410 will continue to receive limited software support from Meraki until Q3 2029.


The GPL source code for the MS410 was requested from Meraki in March 2025, and at the time of writing Meraki has not provided any of the requested source code or an ETA on when they will comply.


Model Meraki Board Part number
MS410-16 Wolfcastle 600-44010
MS410-32 Wolfcastle 600-44020

Meraki MS425 hardware overview

The Meraki MS425 series switches (codename “Hungry Hungry Hippo”) offer 16 or 32 ports of 10Gbit SFP+ Ethernet, two 40Gbit QSFP+ stacking ports, and a Gigabit Ethernet management port.

Meraki MS425-16 Switch with cover removed

Meraki MS425-16 internal view

The MS425 was discontinued in June 2024, and is too old to support secure boot.

Here is a quick summary of the MS425 specs:

  • Broadcom BCM56854 “Trident II” ASIC
  • Broadcom BCM5862x “StrataGX” management CPU
  • 16MB of SPI flash (MX25L12805D)
  • 2GB DDR3 RAM (soldered)
  • 1024MB NAND flash (Micron MT29F8G08ABACA; PDF datasheet)
  • MA-PWR-250WAC (identical to PWR-C2-250WAC)

The UART header in the MS425 is CONN7 (silk screen: UART Console) and follows the standard Meraki UART pinout (1: 3.3V Vcc, 2: Tx, 3: Rx, 4: GND) at 115200 baud.

The MS425-16 uses the same PCB as the MS425-32, but missing 16 SFP+ cages and two PHYs. This is the same technique Meraki used for the MS420-24 model.


The stock Meraki boot process uses u-boot on SPI to load a “bootkernel” (also from SPI), which then initializes NAND and using kexec boots the main firmware. The firmware layout follows the standard Meraki practice of having A/B firmware images: bootkernel1, bootkernel2, part.safe, part.old.

The firmware layout on SPI is:

0x000000-0x100000 : "uboot"
0x100000-0x800000 : "bootkernel1"
0x800000-0xf00000 : "bootkernel2"

Unlike the MS350, the management plane is not an x86 CPU, but a Broadcom “StrataGX” ARMv7. The MS425 runs the same firmware release (switch-arm) as the MS210/MS225/MS250 series.

PCI devices present:

00:00.0 PCI bridge: Broadcom Inc. and subsidiaries Device 8025 (rev 12)
01:00.0 Ethernet controller: Broadcom Inc. and subsidiaries Device b854 (rev 03)

The Broadcom SDK series implements the packet engine in userspace, using the GPL-licensed linux_kernel_bde and linux_user_bde kernel modules to interface with the ASIC. In the Meraki firmware, the packet engine is a component of the userspace click daemon, which loads the bcm_click shared object during click router initialisation.


Similar to the MS420, the three 40mm system fans in the MS425 are controlled by an onsemi ADT7473 (PDF datasheet). The MS425 fans have a Meraki part number: MA-FAN-18K (P/N 680-29010) and contain the Delta FFB0412UHN-C (PDF datasheet). These are identical to the Cisco FAN-T1, which can be purchased for considerably less than the Meraki branded part.

The MS425 accepts two hot-swap power supplies (model MA-PWR-250WAC, P/N 640-20010), which in my units are Delta model DPS-250AB-86 with 12V/20.83A output. Note that the MA-PWR-250WAC is physically and electrically compatible with PWR-C2-250WAC. Higher wattage power supplies like the PWR-C2-640WAC and PWR-C2-1025WAC will also power the MS425.

Idle power consumption:
MS425-16: 72W
MS425-32: 78W

Interesting to note is that the Trident II ASIC found in the MS425 supports VxLAN, however this feature is absent from Meraki’s datasheet and does not appear to be supported by their firmware. Apart from 40Gbit stacking ports, there is not much to be gained from the Trident II in the MS425 over the Trident+ in the MS420: idle power consumption is slightly lower, and it is still supported (see note below).

Meraki have chosen to EoL all of their Broadcom based switches. Being a Broadcom design, the MS425 was axed from the product portfolio on 2024-06-24. The MS425 will continue to receive limited software support from Meraki until Q3 2029. Big “we cancelled all our contracts with Broadcom and are now a Marvell/Catalyst shop” energy.


The GPL source code for the MS425 was requested from Meraki in December 2023, and at the time of writing Meraki has not provided any of the requested source code.

“[F]ulfilling your requests are an important priority for [Meraki]” so I am sure they will comply with their license obligations… Any day now… Just wait for it… It is almost as if they know that providing the GPL source code would enable people to re-use claimed/EOL products and are avoiding doing that. 🤔


Model Meraki Board Part number
MS425-16 Hungry Hungry Hippo 600-45010
MS425-32 Hungry Hungry Hippo 600-45015, 600-45020

Meraki MS420 hardware overview

The Meraki MS420 series switches (codename “Fatboy”) offer 24 or 48 ports of 10G SFP+, with a dedicated gigabit Ethernet port for remote management.

The MS420 series does not support dedicated stacking capabilities, although you can always connect multiple switches together via SFP+.

The MS420 was discontinued in 2016, and is too old to support secure boot.

Here is a quick summary of the MS420 specs:

  • Broadcom BCM56840 family “Trident+” ASIC (Product Brief PDF). The BCM56846 is used for both 24 and 48 port models.
  • BCM84754 SFI-to-XFI PHY
  • Freescale P2020E (PowerPC) dual-core management CPU @ 1GHz
  • 128MB NAND (Hynix H27U1G8F2BTR-BC)
  • 2048MB DDR3 ECC RAM (soldered)

Like the PowerPC-based Meraki MX60 and MX80, the MS420-series uses Kernel 3.4.113.

Similar to other Meraki Broadcom-based switches, the MS420 series implements the packet engine in userspace, using the linux_kernel_bde and linux_user_bde kernel modules to interface with the ASIC. In the Meraki firmware, the packet engine is a component of the userspace click daemon, which loads the bcm_click shared object during click router initialisation.

The UART header is CONN4 on the MS420 and follows the standard Meraki UART pinout (1: VCC, 2: Tx, 3: Rx, 4: GND) at 115200 baud.


The u-boot release on the MS420 is 2013.10 and allows interrupting the autoboot with the magic string xyzzy, as found on other older Meraki products before they disabled the boot delay. Therefore, you can interrupt the boot process, although you have only a few seconds to do so:

NAND boot... transfering control to secondary loader
Starting secondary loader ...
Booting U-boot
transfering control


U-Boot 2013.10-g9a6f165 (Mar 11 2016 - 20:09:33)

CPU0:  P2020E, Version: 2.1, (0x80ea0021)
Core:  e500, Version: 5.1, (0x80211051)
Clock Configuration:
       CPU0:1000 MHz, CPU1:1000 MHz, 
       CCB:333.333 MHz,
       DDR:333.333 MHz (666.667 MT/s data rate) (Asynchronous), LBC:41.667 MHz
L1:    D-cache 32 KiB enabled
       I-cache 32 KiB enabled
Board: Fatboy
I2C:   ready
DRAM:  2 GiB (DDR3, 64-bit, CL=6, ECC on)
L2:    512 KiB enabled
NAND:  128 MiB
*** Warning - bad CRC, using default environment

PCIe1: Root Complex, x1, regs @ 0xff70a000
  01:00.0     - 14e4:b846 - Network controller
PCIe1: Bus 00 - 01
PCIe2: Root Complex, no link, regs @ 0xff709000
PCIe2: Bus 02 - 02
In:    serial
Out:   serial
Err:   serial
init GPIO
init REAR FAN I2C to output
register sysled device
Set Fan in Full Speed
Net:   eTSEC1 [PRIME]
autoboot in 3 seconds
LOADER=>

Once you have gained access to the u-boot console it is possible to tftpboot your own payload.


The P2020E boots directly off NAND, without an intermediate “bootkernel” on SPI flash (as is the case on the MS220, MS210/225, and MS350).

Booting is not as straightforward as just creating a FIT image. Similar to the MX80, Meraki have created a custom image format which includes a header with additional data used to validate the integrity of the image.

The layout of the image header for the MS420 is as follows:

Header field Data type (value)
SHA1_MAGIC uint32 (0x8e73ed8a)
DATA_OFFSET int32 (0x0000400)
DATA_LEN int32
SHA1SUM char[20]

0000:00:00.0 PCI bridge: Freescale Semiconductor Inc P2020E (rev 21)
0001:02:00.0 PCI bridge: Freescale Semiconductor Inc P2020E (rev 21)
0001:03:00.0 Ethernet controller: Broadcom Corporation Device b846 (rev 02)

The switch contains a discrete I2C RTC (NXP PCF8563), however there is no battery present so the RTC does not retain the time across power cycles.

rtc-pcf8563 2-0051: low voltage detected, date/time is not reliable.
rtc-pcf8563 2-0051: setting system clock to 2010-03-21 03:00:00 UTC (1269140400)

The four 40mm system fans in the MS420 are controlled by an onsemi ADT7473 (PDF datasheet). It appears that only the internal temperature sensor of the ADT7473 is present (for anyone else wondering, digging into the kernel module reveals that temp1 corresponds to Remote 1 Temperature, temp2 to Local Temperature, and temp3 to Remote 2 Temperature). The Meraki firmware does a respectable job of managing fan speed; after booting and settling, the fans are not quite the 1U screamer as you might expect from such a switch. They are still audible, but it is tolerable and being near the switch does not require an investment in hearing protection.

The MS420 fans have a Meraki part number: FAN-MS420-R (P/N 680-29010). These are identical to the Cisco FAN-T1, which can be purchased for considerably less than the Meraki branded part.

The MS420 accepts two hot-swap power supplies (model PWR-MS420-400AC-R, P/N 640-29010), which in my units are Compuware model CPR-4011-4M1 with 12V/33A and 5Vsb/3A output (combined power 400W) and are 80+ Gold certified:

MS420-24 idle power consumption: ~85W (single PSU)
MS420-48 idle power consumption: ~100W (single PSU)


The GPL source code for the MS420 was requested from Meraki in July 2023 and at the time of writing Meraki has not provided any of the requested source code.

There are other Trident+ switches (like the Arista DCS-7050S) that can be purchased for around $200 USD, and do not require any additional effort to use. Unless you have decommissioned MS420 switches, I would recommend against buying one as there are better options available.


Model Meraki Board Part number
MS420-24 FATBOY 600-29020
MS420-48 FATBOY 600-29010