topic Re: Firmware Request & Stacking Query: Summit X450e-48p (Running 15.2.1.5 and 12.4.2.17) in ExtremeSwitching (EXOS/Switch Engine)

Firmware Request & Stacking Query: Summit X450e-48p (Running 15.2.1.5 and 12.4.2.17)

antt1995 — Wed, 02 Sep 2026 11:49:39 GMT

Hello everyone,

I recently acquired two legacy Summit X450e-48p switches for a project. They are currently running significantly different firmware versions:

Switch 1: ExtremeXOS 15.2.1.5
Switch 2: ExtremeXOS 12.4.2.17

Because these models are End-of-Life (EOL) and the files are no longer hosted on the official Extreme Portal, I am looking for assistance with the following:

Firmware Archive Request: Does anyone happen to have a copy of the final stable release for this hardware generation, ExtremeXOS 15.3.5.2-patch1-19 (along with its matching SSH .xmod package)? Alternatively, a copy of 15.2.1.5 would also work perfectly to align the pair.
Firmware Synchronization: If the files cannot be sourced externally, is there an alternative local method to force these two specific versions to synchronize?
Stacking Behavior: I am planning to purchase stacking cables for these units. If I physically stack them, will the Master switch automatically force a firmware synchronization/downgrade to the backup node across the stack link, or does EXOS require matching firmware versions before a stack can successfully form?

Any help, file shares, or documentation guidance would be greatly appreciated.

Thank you!

Re: Firmware Request & Stacking Query: Summit X450e-48p (Running 15.2.1.5 and 12.4.2.17)

FredrikB-NN2 — Wed, 02 Sep 2026 13:14:40 GMT

A pair of X450-G2-48P-10GE4 for under $80 each would have been a better starting point. EXOS matching is a requirement to form a stack, so there is problem #1. I don't think you can copy the EXOS files from one switch to another. Someone please correct me if I'm wrong. Problem #2 is the built-in battery that retains the config and keeps track of time when powered off. It is replaceable, but likely costs more than you paid for those switches. #3 is the internal power stabilization. Chances are you have bad condensers on the motherboard that will start producing unstable voltage, causing the internal memory and CPU to go haywire. #4 is stacking cables which may also cost more than you already paid. The G2 can use the front panel SFP+ ports for stacking so any cheap DAC or SFP+ can be used.

Where are you located, EU, US...?

Re: Firmware Request & Stacking Query: Summit X450e-48p (Running 15.2.1.5 and 12.4.2.17)

antt1995 — Wed, 02 Sep 2026 17:41:22 GMT

Located in the UK.
#1 Okay
#2&3 Ah that could be a an issue, I am running these off a UPS so that should help them
#4 The Stacking cables I can get for £14 each for a 0.5m

I'm using about 30 ports on each switch for POE so some of the points you have raised could cause some issues,
I will have a Look at the G2 version and see if we can get that to Augment our setup

Re: Firmware Request & Stacking Query: Summit X450e-48p (Running 15.2.1.5 and 12.4.2.17)

peter89jean — Thu, 08 Oct 2026 06:08:34 GMT

ExtremeXOS generally requires matching firmware versions to successfully form a stack, meaning a master switch will not automatically force a downgrade or sync across a mismatched backup node. Since official EOL downloads require an active Extreme Portal account, your best option to align the pair is to copy the running image from your 15.2.1.5 switch via TFTP or SCP using the CLI (download image), install and set it as active on the second switch, and reboot both units before cabling them together for stacking.