Re: multiple-device questions

[Dan Williams <dcbw redhat com>]

On Thu, 2008-05-15 at 02:12 -0600, Andrew Jorgensen wrote:
> What are the plans for UI for controlling multiple-device behavior?

There's an applet re-write on the table for 0.7.1.   The current
menu-based design pretty much falls over for multiple devices.

> Right now nm-applet just connects to all networks that have automatic
> configurations.  This is potentially confusing.  A few people have filed
> bugs or asked questions on this list.

Right; though this isn't so much different than current networking
systems.  If you want complete manual control of your connecitons, then
you don't mark those connections as "autoconnect", and then you get to
manually activate and deactivate those connections as you see fit.

> If the fastest device does not have a gateway defined (none offered by
> DHCP, link-local only, or none configured in static config) will NM
> choose a slower device for the default route?

Yes.

> What signaling is given the listeners (like Pidgin or Evolution) when a
> device goes down but there are other devices up?

As Tambet said, there are two mechanisms:

a) Simple overall network state such as DISCONNECTED, CONNECTING, and
CONNECTED, which is a composite of all the current device states.  If at
least one device is connected and there is a default route, the state
will be CONNECTED.

b) The ActiveConnection API.  Each current connection has an
ActiveConnection object which clients can use to figure out the state of
individual network connections and devices.  Each active connection has
one or more devices assigned to it, and a device cannot be assigned to
more than one active connection.  It's important to remember that NM
deals with _connections_, not really individual devices, though NM does
provide state for individual devices as well.

> Is the signaling different when it's the default route (or not) that has
> gone down?

Yes; you get org.freedesktop.DBus.PropertyChanged signals for the
ActiveConnection objects when their 'default' property changes.  Only
one ActiveConnection object will have a True 'default' property, and
that is the connection that has the default route.

> What if, for example, evolution is connected to a mail server on a
> private network and the default route (on another network) goes down?
> Would it still receive a signal and go offline?

VPN connections are also ActiveConnection objects and will exist for the
lifetime of the VPN connection.  We haven't completely though out how
apps should tie into VPN support, but if the app really wanted to, it
could store the settings service name and connection ID of the VPN
connection it cared about, and track the lifecycle of that VPN
connection.

Dan