On Fri, Oct 30, 2015 at 12:04 AM, Duckworth, Douglas C <duckd@tulane.edu> wrote:
Doug


Hi Doug,
You haven't sated your vdsm/oVirt version so I my answers might be somewhat generic.
1) once a network configuration (net-conf) is given by the engine, and is configured by vdsm,
    vdsm stores it under /var/run/vdsm/netconf/{nets,bonds}. This is used as an intermediate
    place fro this configuration, and allows the user to verify that his requested net-conf
    indeed serves his goals.
    If the worst has happen, and all communication is now broken, and since this path does
    not survive a reboot, it leaves the user with the emergency ultimate option of rebooting
    the host and let it restooe the last knownworking net-conf (see2).
2) once engine calls setSafeNetworkConfig API verb, this info is copied into /var/lib/vdsm/persistence/netconf/
    in an atomic operation. Since this path survives  a host reboot, the host will restore
    all networks from that place.
    If I am not mistaking, the engine defaults to call this API immediately after each netwrok
    setup (it can be toggled in a checkbox in the UI).

In general, the ultimate knoledge about the required networks sits in the administrator mind,
and hopefully, in the engine database. So the best options you guys have is adding the required netwroks
one by one from the engine, and call setSafeNetworkConfig after each verified successful state.
This will ensure a proper state+backup on your host.

--
Thanks,
Ido Barkan