Help: how I make a virtual floopy disk? Booting Linux on Mobile Phone
 

Hi everybody,


I am trying to make a virtual bootable linux floopy to use it with a virtual machine jpc : "www-jpc.physics.ox.ac.uk" , it is a virtaul machine written in java and run also on mobile phones symbian.
Okay, what I want to do is to boot a small linux distributions which are an .img file
like "Fd Linux" or many others nulinux etc.. but the problem is I dnt know how to make a virtual node or floopy under linux. the floopy.img file wich come with jpc is a freedos img file and it boots well on my mobile! I wanted to replace that floopy.img freedos by a linux .img file but I dnt know how to make it bootable.. can you help?

to try what I mean you can download the jpc for mobile from here : "mosh.nokia.com/content/3F87BC10B48ADD1AE040050AEE0429F8"

thanx

hi all,
could you help please! I am checking my post every hour.. no reply yet :(

anybody home!?

hello!? where are linux professionals?? is my question so difficult!?

The question is not clear. A "virtual floppy disk" sounds like something in the virtual machine. I suspect that what you want to do is create and/or mount a disk image using a loopback filesystem?

thanx for your reply,
actualy I tried the mount command with the loop option before but it mounts only some .img files. the jpc is a virtual machine indeed and it accept a .img file but it should be bootable! jpc indeed boots freedos and I mounted the floppy.img file which come with it ( look at my second link in my 1st post above)and I can view add delette files from it and then unmount it.. the problem is: I want to boot a small linux distributions instead of freedos, the .img files what I found in the net are all comes with the rawrite.exe (for windows to create a bootdisk) or to use the command "dd .." but I want a way to use the dd command and create the result in a file instead of a /dev/fd0 because I dnt have diskete in my computer and its not really needed because I boot a virtual machine not a real machine itself. for example fdlinux & co in their README they said you have to use dd if=.. etc to create the bootdisk .. but me I want to create a virtual diskete ( a file which I will name it floppy.img and then pass it to jpc to boot it) to use it with jpc .. or maybe just need to use the mount command and then I have to add or do something to make the final .img file bootable. is it little clear now ?! :)

thanx

Paragraphs would help :-)

When you say it boots the image which came with it, what do you mean? Is there some setting in the VM to select an image to use? If so, can you mount this image (which works with the VM) using a loopback filesystem in Linux?

I would imagine two explanations for your VM software not being able to boot other disk images:

1. It doesn't understand the image file format which Linux distros use for floppy images (which is a byte by byte copy of the whole block device). If the image you got with the VM is not mountable with a loopback device inside Linux, this is probably the explanation.
2. The VM will boot from images of DOS/VFAT filesystems and maybe others, but not EXT2, which is the filesystem which Linux distro floppy images tend to use.

In either case, I don't think this is so much a Linux issue as a question for the developer of the VM... ask them why you can't boot a Linux boot floppy. Some VMs don't fully implement a virtual machine, instead they make assumptions about the OS which is running and take shortcuts.

The jpc can boot both linux and dos. in the links I gave there is the source code you can check it. the linux which come with it has a file called linux.img and it boot it. but is 10M quite big for a phone to boot it. thats why I choosed to boot a linux which has a size of a floopy like the file floppy.img ( freedos) which come with the jpc for mobile. the file should be named floppy.img because its hardcoded. but thats not a problem because you can change it in the source code and recompile it with any name. you should know that there are 3 zip file in their home page : jpcSource.zip ( source code for the whole virtual machine), jpcLinux.zip ( this one only binary class files with a linux.img file, thsis is an applet and you can load any img file you want from the applet menu) and then jpcmobile( from the second link in my 1st post , this one has also the class files and the file floppy.img which contain the freedos , this is a midlet).

my problem is : i didnt find any linux image .img file which boot automatically (like freedos floppy.img) without using that command dd if = .. etc which comes in the README of any small linux distro or mounting. and if so how I use the dd command or mount to create a bootable file .img which I will call it floppy.img and pass it to the jpc virtaul machine mobile..!

mathieu , did you try it?

Hi.

I also have a server without a floppy drive, and I needed to use a boot floppy to get BeOS 5 Pro installed. VMWare server has an option to boot from a floppy image (a virtual drive), so I simply copied the floppy image to a file on the VMWare host, told the new VM to use that file as a virtual drive, and it worked. The procedure in VMWare for creating a new virtual machine allows one to add devices -- disks, floppies, etc., -- which are then handled by the virtualization.

Sorry I don't know any of the mechanics behind this and I don't know about the VM system you are using, but perhaps it has a feature similar to VMWare that you have over-looked.

Best wishes ... cheers, makyo

(Sadly the BeOS is apparently too old to have drivers for the virtual video card, so I won't be using it, but it was a good learning experience, because apparently I'll be needing this virtual floppy scheme for installing GNU/Debian Hurd.)