Trying to convert an old hand-rolled bonding configuration to NetworkManager

[Andrew Mahone <andrew mahone gmail com>]

For a while now I've had my ethernet and wifi devices bonded in
active-backup mode, such that (on my home network, where they're
bridged) I can seamlessly unplug and retain my IP address and all
active connections, losing only speed. I've installed the latest
NetworkManager from git, and I'm trying to replicate this setup with
NM. I run Arch, which installed a NetworkManager.conf that uses the
keyfile plugin. There doesn't seem to be any documentation describing
the use of anything but the ifcfg-rh plugin - can this even be
expected to work?

I have a bonding connection set up with type=bond, and a bond section
in its config:
[bond]
interface-name=bond0
mode=active-backup

But nm-cli reports the mode as balance-rr. Similarly, the slave
devices have connections set up with master=bond0 and slave-type=bond.
These seem to work, in that I get the expected error if I try to apply
any IP configuration to the slaves directly, but I can see that NM
tries to bring up the master without ever enslaving the slave
interfaces, and DHCP fails since it has no slaves.

Is there something I'm missing? The keyfile plugin is supposed to
handle all possible options according to the documentation, but the
mapping between it and sample configurations for other plugins is not
always clear.
-- 
Andrew Mahone
andrew DOT mahone AT gmail DOT com