Floppinux ā An Embedded Linux on a Single Floppy, 2025 Edition
221 points - today at 4:33 AM
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The two main problems I ran into were 1) software support at the application layer, and 2) video driver support. There is a herculean effort on the part of package maintainers to build software for distros, and no one has been building 32 bit version of software for years, even if it is possible to build from source. There is only a very limited set of software you can use, even CLI software because so many things are built with 64 bit dependencies. Secondly, old video card drivers are being dropped from the kernel. This means all you have is basic VGA "safe-mode" level support, which isn't even fast enough to play an MPEG2. My final try was to install Debian 5, which was period correct and had support for my hardware, but the live CDs of the the time were not hybrid so the ISO could not boot from USB. I didn't have a burner so I finally gave up.
So I think these types of projects are fun for a proof of concept, but unfortunately are never going to give life to old computers.
From the main page:
As with most things in the GNU/Linux community, this project continues to stand on the shoulders of giants. I am just one guy without a CS degree, so for now, this project is based on antiX 23 i386. AntiX is a fantastic distribution that I think shares much of the same spirit as the original DSL project. AntiX shares pedigree with MEPIS and also leans heavily on the geniuses at Debian. So, this project stands on the shoulders of giants. In other words, DSL 2024 is a humble little project!
Though it may seem comparably ridiculous that 700MB is small in 2024 when DSL was 50MB in 2002, Iāve done a lot of hunting to find small footprint applications, and I had to do some tricks to get a workable desktop into the 700MB limit. To get the size down the ISO currently reduced full language support for German, English, French, Spanish, Portuguese and Brazilian Portuguese (de_DE, en_AU, en_GB, en_US, es_ES, fr_FR, es_ES, pt_PT, & pt_BR ). I had to strip the source codes, many man pages, and documentation out. I do provide a download script that will restore all the missing files, and so far, it seems to be working well.
Sadly, it does not seem to boot on my 486 DX2, I even stuffed 32M of RAM into the machine (8*4M, maximum the mainboard supports), more than the recommended 20M.
I have copied the floppy image from the site. It churns for about a minute and a half, loading kernel and initrd, then says "Booting kernel failed: Invalid Argument" and drops into SYSLINUX prompt.
EDIT: I tried a few more floppies to rule that out as the cause of the problem.
Here are some screenshots: https://imgur.com/a/floppinux-0-3-1-Mdh1c0w
EDIT 2: I cloned SYSLINUX, checked out the specific commit and did some prodding around.
The function `bios_boot_linux` in `com32/lib/syslinux/load_linux.c` initializes errno to EINVAL. Besides sanity checking the header of the kernel image, there are a few other error paths that also `goto bail;` without changing errno.
Those other error paths all seem to be related to handling the memory map. I know that the BIOS in my machine does not support the E820h routine. I have a hunch that this might be the reason why it fails.
The website has an image gallery where people ran it on actual hardware: https://krzysztofjankowski.com/floppinux/floppinux-in-the-wi...
Most of those machines seem to be newer systems which probably support E820h, except for another 486 DX2 with a similar vintage as mine, that also failed to boot.
I don't know if that's also true for data integrity on physical magnetic media. FAT12 is not a journaling filesystem. On a modern drive, a crash during a write is at best, annoying while on a 3.5" floppy with a 33mhz CPU, a write operation blocks for a perceptible amount of time. If the user hits the power switch or the kernel panics while the heads are moving or the FAT is updating, that disk is gone. The article mentions sync, but sync on a floppy drive is an agonizingly slow operation that users might interrupt.
Given the 253KiB free space constraint, I wonder if a better approach would be treating the free space as a raw block device or a tiny appended partition using a log-structured filesystem designed for slow media (like a stripped down JFFS2 or something), though that might require too many kernel modules.
Has anyone out there experimented with appending a tar archive to the end of the initramfs image inplace for persistence, rather than mounting the raw FAT filesystem? It might be safer to serialize writes only on shutdown, would love more thoughts on this.
This could be increased noticeably by using one of the common extended floppy formats. The 21-sectors-per-track format used by MS¹ for Windows 95's floppy distribution was widely supported enough by drives (and found to be reliable enough on standard disks) that they considered it safe for mass use, and gave 1680KB instead of the 1440Kb offered by the standard 18-sector layout. The standard floppy formatting tools for Linux support creating such layouts.
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[1] There was some suggestion² that MS invented the extended floppy format, they were sometimes called āwindows formatā, but it³ had been used elsewhere for some time before MS used them for Windows and Office.
[2] I'm not sure if this came from MS themselves, or was invented by the tech press.
[3] and even further extended formats, including 1720KByte by squeezing in two extra tracks as well as more data per track which IIRC was used for OS/2 install floppies.
oh god
As an alternative, isn't ext2 smaller by having no FAT tables?
https://www.zelow.no/floppyfw/
to setup small router on 486 with 12 MB ram and run flawless. Later i get Linksys WRT54GL and decommissioned that machine.
And they used to fail all the time, especially when you had something that spanned more than a single disk.