On Thu, Jul 26, 2012 at 9:21 AM, anatoly techtonik <techto...@gmail.com> wrote: > On Wed, Jul 25, 2012 at 6:00 PM, Stefan Hajnoczi <stefa...@gmail.com> wrote: >> On Tue, Jul 24, 2012 at 8:02 PM, anatoly techtonik <techto...@gmail.com> >> wrote: >>> On Tue, Jul 24, 2012 at 1:23 PM, Stefan Hajnoczi <stefa...@gmail.com> wrote: >>>> On Mon, Jul 23, 2012 at 10:41 PM, anatoly techtonik <techto...@gmail.com> >>>> wrote: >>>> A -netdev needs to be paired with a NIC -device. That's why the >>>> identifier is essential, it allows you to say -netdev >>>> <type>,id=netdev0 -device <type>,netdev=netdev0. >>> >>> It still says "The id option can be used with the -device...", where >>> "can be" looks like it should be replaced by "must". >> >> Strictly speaking "can be" is correct because -device id= is optional. >> You can also do: >> -net user -device virtio-net-pci,vlan=0 >> >> This is basically equivalent to: >> -net user -net nic,model=virtio > > -net user is deprecated, no?
Yes. What I'm showing is that you can use -device without a netdev's id. So it isn't a "must" as you asked above. But I think this detail is not helpful on the Networking wiki page. The wiki edit I did yesterday removes the issue entirely. >> What's going on here is that -device is used but with the legacy QEMU >> "VLAN" feature that can be used to connect NICs and backends. >> >> Things aren't as simple as they should be but I think the problem here >> is really the documentation. We can try to improve it so that it >> doesn't leave open questions like this, maybe without going into every >> nasty detail. > > Yes, it would be nice if documentation was user story oriented, going > gradually from the simplest use stories (tutorials) to more difficult: > 1. download stuff from internet from guest (NAT) (OS updates, software > installation) > 2. run services on guest accessible from host (web server and stuff) > without specialized configuration (i.e. port forwarding) > 3. services on guest accessible from other guests (web development > scenarios - guest servers for db, web, client on host) > .. > x. routers, vlans, networks, bridges and other hardcore hardware emulation > stuff Absolutely. Especially a quickstart would be handy. For many people it's not necessary to understand how QEMU networking works, they just want their VM to access the internet. >>> Why is it impossible for -netdev to create NIC device automatically if >>> not explicitly set? As a user I don't really know which net device do >>> I need. This would greatly simplify user experience (and lower Qemu >>> bounce rate). >> >> There was a similar discussion about -drive for block devices just the >> other day. I don't think there's a good answer except that QEMU >> command-line has historic baggage and that everyone has a different >> use case so it can be hard to come up with a good simplified >> command-line option set. > > Do you maintain a list of use cases? It should be easy to forward > people to it when they face with this problem on not-intuitive > interface. Then outsiders can try to help with prototyping this > interface too. For example, with Python's argparse. I'm not aware of a list, sorry. Stefan
