booting another system from running linux (kexec)

[Gerd v. Egidy]

Hi,

I want to create a central disk image management for lots of clients. Theses 
clients should be able to boot into different OS. The OS is cached on the 
local disk but should be updated via rsync at boot time.

One solution would be:

1. boot a linux kernel (via PXE)
2. execute some programs (update the disk images via rsync)
3. show a boot menu (execute a grub program to show the regular grub boot 
menu, with or without splashscreen)
4. boot into the selected system (maybe via the new kexec system call)

The system to boot into should not be limited, e.g. different linux distros, 
*bsd, dos, windows,...

I think currently steps 3 and 4 are not implemented. Are there plans for 
making something like this possible?

Another way to solve this would be to add scripting, dhcp, rsync and writing 
to linux-fs/ntfs directly into grub. But I think that is a huge task and not 
flexible enough.

Or do you guys have better ideas?

Kind regards,

Gerd