Re: [Qemu-devel] Problem with `change' monitor command

["Daniel P. Berrange" <berrange@redhat.com>]

On Wed, Sep 17, 2008 at 01:46:13PM +0200, Robert Riebisch wrote:
> Hi!
> 
> I'm using QEMU 0.9.1 and SVN on Win32 to emulate an x86 PC environment.
> 
> With `change floppy0 foo.img' I'm able to use another floppy image on
> the fly, but this will only work, if the new floppy image is of the same
> size as the old one. Switching from, e.g., 1.44M to 2.88M is not
> recognized by the guest OS. Even rebooting the VM doesn't help, because
> CMOS value 0x10 ("Floppy Drive Type") won't be adjusted.
> (http://www.brl.ntt.co.jp/people/takehiko/interrupt/CMOS.LST.txt)
> 
> This is also a big problem when you omit "-fda bar.img" from the command
> line. You can still change the image file in QEMU monitor, but guest OS
> (here: DOS) will never recognize it, because CMOS value 0x10 still holds
> "0" (= "none" for floppy0 and floppy1). Btw: It would be more
> consistently to also change command-line option "-fda" to "-floppy0".

The -fdXX, -hdXX, etc args are all legacy syntax. The recommended way
to specify disks is via the -drive parameter, so no change to -floppy0
is required.

Daniel
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