Comment 7 for bug 1050433

Reviewed: https://review.openstack.org/19126
Committed: http://github.com/openstack/nova/commit/3f513aa1e408f762867d9cd7c64ffde68f960437
Submitter: Jenkins
Branch: master

commit 3f513aa1e408f762867d9cd7c64ffde68f960437
Author: Daniel P. Berrange <email address hidden>
Date: Mon Dec 17 20:27:50 2012 +0000

    Merge LibvirtHybridOVSBridgeDriver into LibvirtGenericVIFDriver

    The LibvirtHybridOVSBridgeDriver VIF driver and the
    LibvirtOpenVswitchDriver VIF driver both support OpenVswitch
    based guest configs. The difference is that the hybrid driver
    does not connect the VM directly to the OVS bridge. Instead it
    connects the guest to a private Linux bridge, connected to the
    OVS bridge via a veth pair. This allows iptables firewall rules
    to be applied to the guest VIF. The hybrid driver should always
    be used unless the admin has disabled Nova firewalls using the
    NoopFirewallDriver impl. Rather than require the admin to figure
    this out themselves, pick the right impl automatically based
    on the configured firewall driver.

    When Quantum gains support for firewalling, it will need to be
    able to inform Nova whether it has got a filtering applied to
    the VIFs, and thus let Nova intelligently skip its own attempt
    at filtering.

    The LibvirtGenericVIFDriver class can use the 'vif_type' mapping
    field to determine whether an OVS network configuration is
    required. In combination with a check against the firewall
    driver, a dedicated driver for OVS hybrid setup is no longer
    required.

    The LibvirtHybridOVSBridgeDriver class functionality is
    merged into LibvirtGenericVIFDriver. For backwards compatibility
    with the Folsom release, the existing LibvirtHybridOVSBridgeDriver
    class is made to inherit from LibvirtGenericVIFDriver and directly
    call the bridge specific setup APIs. This eases migration to
    the new VIF impl during the Grizzly deployment lifecycle, with
    an expectation that the LibvirtHybridOVSBridgeDriver stub
    will be deleted after the Havana release.

    Bug: 1050433
    Blueprint: libvirt-vif-driver
    Change-Id: I93294409a75aaa15d297471ab3e600c3c124bcde
    Signed-off-by: Daniel P. Berrange <email address hidden>