Re: [Qemu-devel] Qemu sandbox for teaching

[Henrik Nordstrom]

On Sat, 28 May 2005, Jerome Warnier wrote:

> Advantages of every solution:
> - UML is fast to run and pretty safe

If you give out root rights UML is only as safe as the account the UML 
kernel runs as.

> Problems of every solution:
> - qemu is slow, and a lot of virtual machines at the same time on the
> same machine will slow it down and use too much memory, I think (I'm
> talking about 10 people ?playing? at the same time). Using only a
> text-mode virtual machine may probably help, though

Only text-mode helps a lot.

> - chroot does not allow much and may take time to setup correctly

chroot and allowing root rights is a no-no. The root user within a chroot 
is still root.

> - UML is difficult to setup, and needs a kernel patch (even on 2.6?) to
> work

UML doesn't require a kernel patch but it performs significantly better 
if you do.

Similar for qemu with it's kqemu kernel module, but here only a custom 
module is required no patching of the main kernel.

I would go for qemu (with kqemu), tun/tap networking with proxy-arp or 
explicit routing and a java applet SSH (or perhaps telnet) client to 
connect.

Regards
Henrik