[et-mgmt-tools] [PATCH] Add usermode networking to the list of available network types

[Daniel P. Berrange]

On Wed, Jan 16, 2008 at 11:43:23AM -0500, Cole Robinson wrote:
> Daniel P. Berrange wrote:
> > On Wed, Jan 16, 2008 at 10:31:27AM +0100, Soren Hansen wrote:
> >> It's perfectly reasonable for privileged users to want to use usermode
> >> networking, but currently, there's no way for them to do that. The
> >> attached patch fixes this.
> > 
> > NACK, it offers nothing of benefit over the existing virtual networking
> > which already provides a NAT based isolated network. Usermode networking
> > is a crude hack which is frankly utter rubbish - the only option you
> > have if you're an unprivileged user, but no privleged user should be
> > using it. Usermode networking is also not 64-bit cleanup & will often
> > corrupt / drop traffic. Just say no if you're privileged.
> > 
> > Dan.
> 
> Regardless of the NACK, there are still some issues we may want to consider.
> By not exposing usermode as an option and just setting it up by default, users
> can't specify a mac address for the interface, and if they remove it from the
> guest, there is no option to add it back. The latter could be hacked up easily
> I suppose, so there really aren't dealbreakers, just things to consider.

There is no point choosing a MAC address if you're using user mode network
because you don't have any control over usermode network stack. It always
give you the same IP addr, all outgoing traffic gets sent out with the 
MAC of the host because of the way Slirp works.

Dan.
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