Is Gentoo x86 486 compatible?

[Ciff]

Well as the topic asks... will this work out?

I'd like to hear you guys' opinions first, before I invest quite a bit of time into such a project.
Thing is, this is a project of heart. : ) - Of course it makes no sense at all, I know, but what about the good old "what-if" style of a discussion. :>

I've got my 486er DX2-66 sorted and running again, refurbished the internal and external parts, successfully installed DOS 5.0, upgraded to 6.0 and then to 6.22 (to keep dosshell and co on board), installed OS/2 Warp 3 (as it is quite a 1993'ish kind of a setup) - Feels like in the old days. Very sweet.

NOW! I'd like to create an image of my HDD, which is kind of a hazzle. I need something to boot from, in order to "not touch" the HDD but still get a hand full of nice tools for imaging, mounting samba locations, etc. (like for instance partimage, dd, mount.cifs, msdos & HPFS file system support)
Of course I could simply take out the hard drive, and image this thing on another machine which still has an IDE port or some USB adapter for IDE. - Sure. But I'm a very lazy but at the same time curious person. - So I do NOT want to get up and open up the case. Instead I'd like to create a (set? of) linux boot floppies using gentoo which give me these tools at hand on my 486er, that can only boot from hdd or floppy drive. (Yes, 1.445 MB floppies are supported :>)

On my web search I found some old 1998 documents on how to create such a thing... but will [THIS] still work?

Thanks for reading and thinking.. : ]

[Jaglover]

I wouldn't know how to create such a floppy using modern Gentoo. More I think about it less possible it seems. Anyhow, http://www.linuxlinks.com/Distributions/Floppy/
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[NeddySeagoon]

Ciff,

A modern gcc can emit 486 code if you ask it nicely but you need somewhere to run it.
That somewhere probably needs to be another Gentoo.

Are you expecting to boot linux from floppy?
You will need to find an old kernel to have it even fit on a floppy.

I still have Red Hat 6.1 or 6.2 from 1999 that comes with boot floppy images, it works on a i386.
They are only aimed at allowing you to install Red Hat though.
I can host the whole DVD if you want.

There might even be an old Gentoo CD that you can arrange to boot with MSDOS and loadlin.
I've never tried that. You will need an optical drive though.

Your link will still work if you can find old enough kernel sources to fit the compressed kernel onto a floppy.
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Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[Jaglover]

I was thinking about kernel, to build that old kernel probably an ancient GCC is needed, like 2.95. I'd be surprised if it built with modern GCC.
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[Ciff]

@NeddySeagoon: Given that I can provide another Gentoo machine (AthlonXP though), will GCC be able to cross-compile to 486er compatible code from there? Or do I need to compile this stuff on a real 486er running gentoo?

> Are you expecting to boot linux from floppy?
Yes, as this 486er can only boot from floppy or hard drive. (BIOS option only allows to switch between "A, C" and "C, A".
The aim is to have a floppy disk at hand, which gives me access to mount.cifs, partimage and dd.
Could an up2date kernel fit onto a floppy disk, when I only select stuff that the 486 actually has? - Like a boot disk, made for this machine only.

Good idea @RedHat! I also remember having SuSE 6.x and 8.x somewhere, which I remember also had floppy boot support, but not sure anymore which tools were on these disks.. going to find out later on today. : ) - Cewl!


@Jaglover: Yes, this is all quite complicated.. a new kernel would most likely not support this old hardware anymore, and an old kernel might not be processable through a compiler from today.. so I might need an old kernel and an old gcc from back then.
Beginning to see that it might indeed be better to open the case, take the hdd out and image it on another machine hehe.. but not giving up yet.. :>

[Jaglover]

Your best bet is to get one of those Linux floppy distros or use an old Linux to create boot disk, I seem to recall there was a makebootdisk application (or similar) which created a floppy image. You can compile for i486 in your Gentoo box, just set the -march, you don't even need it for kernel. I do not think a modern kernel will fit a floppy, plus you need space for your applications. Drop partimage, dd can do it.
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[NeddySeagoon]

The root filesystem can be on a second floppy.
I recall the kernel loading, swapping floppies and pressing the 'any key' to continue.

You will end up with an old kernel, to get it to fit on a floppy, even compressed.
The old kernel won't support a modern glibc and almost every app needs glibc, so you are on a slippery slope that starts with an old glibc, just to get the kernel and glibc to play nicely.

De you really want to do this piece of industrial archaeology yourself or use a ready to run floppy distro?
If you have a non bootable optical drive, you can boot the kernel from floppy and have a read only root on CD.
Actually, there was a hack to partition a CD-RW into a conventional read only part and a packet written part, so you had writeable space on the CD-RW too.

As Jaglover says, -march=i486 will get you code that actually runs on an i486 but you really don't want to install it on your build host.
Particularly, when you build things that will break the build host. You need to make an i486 chroot to contain the damage.
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Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

[Ciff]

Okay. I see.. resurrecting dinosaurs is not the easiest thing to do.. ; ) - I'll try to go with an already made floppy disk and look for one that can do most of what I am looking for. : )

Big thanks you two!!

[TheLexx]

If your using a PATA HD, why not just install Gentoo onto the HD using a desktop computer. I have an old MB that has both PATA and SATA ports. And even if you don't have a PATA port you can get an old promise card with an PATA port. Or you can use an PATA <-> SATA converter sold on eBay for $5 or less.

[Ciff]

Hiyya Lexx!

That's something that I could have done, indeed. : )) hehe
Solved it another way now..

Deep in the shelf I found an old SuSE Linux 6.0 from the good old 1998ish days. In the package there is a boot floppy (very handy now), and a package of 5 CDs. The first 4 CDs contain the installable version of SusE 6.0. But the fifth CD holds a live system.
Now using the boot floppy, I can then access the live cd, and therefore get to a point where I have LAN, smb tools, dd and stuff accessible.

That's the solution to go for me now.

[pcmaster]

Try one of the boot disks from slackware: http://www.slackware.com/install/bootdisk.php
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pcmaster