Hi all, Is it possible to take the 686 CentOS 5, install that in virtual machine, install a custom kernel that is the 486 flavor, take that image and put it on a 8G CF card - insert that into a small form factor 486 class machine and have that work? I am hoping the extra instructions in a 686 (MMX, SEE etc) are not used by any libraries that I would be using (just standard stuff) and the new 486 compiled kernel would not be using those instructions either. Can this possible work? I am hoping to not use debian i386 basically. Thanks, Jerry
When you create a virtual machine don't you have a choice of what type of processor you want and so forth? That would be the clean way to do it would it not? -- ?Don't eat anything you've ever seen advertised on TV? - Michael Pollan, author of "In Defense of Food"
Jerry Geis wrote:> Hi all, > > Is it possible to take the 686 CentOS 5, install that in virtual machine, > install a custom kernel that is the 486 flavor, take that image and > put it on a 8G CF card - insert that into a small form factor 486 class > machine and have that work? > > I am hoping the extra instructions in a 686 (MMX, SEE etc) are not used > by any libraries > that I would be using (just standard stuff) and the new 486 compiled > kernel would not be > using those instructions either. > > Can this possible work? I am hoping to not use debian i386 basically. >first, you'd need to reconfigure that linux running in a VM to run in whatever hardware your embedded platform provides (network, disk, etc). second, you'd not only need a new kernel, but also any usermode packages that are -i686 or -i586 would need recompiling. there's more than you might think. check out http://www.damnsmalllinux.org/ that will run on nearly -anything- with very minimal resources. the standard version fits on a 50MB live mini-CD (those credit card shaped things).
> > It may be one way to do it, but that is not how xen or kvm are > ordinarily set up under CentOS -- qemu has (had) the hooks to > simulate the missing opcodes of some arch's, but at a > performance penalty >if there is a way to "simulate" missing opcodes in the kernel - that would be great also. I dont care if there is a performace hit. I am looking for a way to run the 686 centos on a 486 machine. I was hoping I could just recompile the kernel as 486 and any libraries would not be using MMX/SSE etc... Looking for any solution. Jerry
On Tue, 8 Dec 2009, Jerry Geis wrote:> Looking for any solution.how deep is your wallet ;) I would just find a 486 out in the boneyard. As I still have a RHL 4.2 486/33 s/ 16 meg of ram in daily service, I know just what machine to pull and replace -- Russ herrold
At Tue, 08 Dec 2009 14:02:28 -0500 CentOS mailing list <centos at centos.org> wrote:> > Hi all, > > Is it possible to take the 686 CentOS 5, install that in virtual machine, > install a custom kernel that is the 486 flavor, take that image and > put it on a 8G CF card - insert that into a small form factor 486 class > machine and have that work?Will this small form factor 486 class machine be on the public internet network? If not (and thus not needing any current security patches, etc.), you might consider install RH 7.3 on it. RH 7.3 includes a *stock* i386 2.4 kernel (RedHat never built i486 kernels and I am not sure if anyone else bothered to either). I would also guess that the small form factor 486 class machine probably is NOT going to have modern I/O items, so you *probably* won't need any new kernel modules (eg SATA or fancy video or sound or network cards, etc.). I fould a set of RH 7.3 CDs on-line (*one* of the old mirrors still has it on line: ftp://mirror.atlantic.net/pub/redhat-archive/7.3/ And I snarfed the ISOs to my server: ftp://ftp.deepsoft.com/pub/RH7.3/iso/i386/ (I have an interst in using RH 7.3 on old '486 boxes and use them as model RR control nodes.)> > I am hoping the extra instructions in a 686 (MMX, SEE etc) are not used > by any librariesOnly some libraries (glibc for one, but it is available in several 'flavors', I think including a vanila i386 flavor).> that I would be using (just standard stuff) and the new 486 compiled > kernel would not be > using those instructions either. > > Can this possible work? I am hoping to not use debian i386 basically.Since various packages that would be installed on a 686 machine would be built for the 686 arch, you can't just copy the image of the 686 install onto a 486 system. You'll need to do a re-install to a 486 target. You can rebuild the kernel on the 686 (virtual or otherwise) and I believe all of the *.i686.rpm's are available as *.i386.rpm's. Somehow you will need to hack things at the install level to force a plain i386 install. You might need to hack anaconda and insert the i386 kernel or some such. Or do a careful downgrade of all of the i686 packages to i386 packages (in addition to the kernel itself).> > Thanks, > > Jerry > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > >-- Robert Heller -- 978-544-6933 Deepwoods Software -- Download the Model Railroad System http://www.deepsoft.com/ -- Binaries for Linux and MS-Windows heller at deepsoft.com -- http://www.deepsoft.com/ModelRailroadSystem/
----- "Marko Vojinovic" <vvmarko at gmail.com> wrote:> On Tuesday 08 December 2009 19:54:03 Jerry Geis wrote: > > > It may be one way to do it, but that is not how xen or kvm are > > > ordinarily set up under CentOS -- qemu has (had) the hooks to > > > simulate the missing opcodes of some arch's, but at a > > > performance penalty > > > > if there is a way to "simulate" missing opcodes in the kernel - that > would > > be great also. I dont care if there is a performace hit. > > > > I am looking for a way to run the 686 centos on a 486 machine. > > I was hoping I could just recompile the kernel as 486 and any > libraries > > would not be using MMX/SSE etc... > > I am no expert on this, but have a feeling that you would basically > need to > recompile every package that does not have an .i386 rpm. > > And if you are about to recompile things, why not use gentoo or > something like > that?Gentoo? What do you have against the OP? Why subject him to such madness and unnecessary pain? :D In my recent trip through i486 land, I found that Debian seems to be the best bet for nearly all packages being natively available in i386. Also, the installation can be pruned down to a very slim ~140MB if you're careful. Tim Nelson Systems/Network Support Rockbochs Inc. (218)727-4332 x105