Comment 5 for bug 1681758

Reviewed: https://review.openstack.org/474241
Committed: https://git.openstack.org/cgit/openstack/nova-lxd/commit/?id=78b6c14f2cf375493f3fc268d589f2ba23f4f346
Submitter: Jenkins
Branch: master

commit 78b6c14f2cf375493f3fc268d589f2ba23f4f346
Author: James Page <email address hidden>
Date: Wed Jun 14 15:57:47 2017 +0100

    vif: redux interface wiring approach

    The nova-lxd driver has to take a slightly different approach
    to virtual interface wiring due to a lack of an equivalent to
    'launch and pause' in LXD.

    For some interface types, the last mile tap device needs to
    be present for vif plugging to complete successfully which
    occurs prior to the instance being launched; This change
    refactors the vif module to create veth pairs directly
    in nova-lxd, rather than delegating this to LXD as part of
    a bridged network interface type. This allows vif plugging
    to complete prior to the instance being created in LXD.

    The side effect of this change is that all currently supported
    interface types are now configured as 'physical' interfaces
    in LXD profiles for instances - wiring to bridges is handled
    directly by the nova-lxd driver instead.

    This change has been validated with:

       ovs driver + iptables hybrid firewall driver
       ovs driver + openvswitch native firewall driver
       linuxbridge driver + iptables hybrid firewall driver

    The VIF wiring approach is described in detail in the VIF
    wiring documentation included in this change.

    Closes-Bug: 1681758
    Change-Id: Ic268e989d1ee19f696298fb1e0db729a00352a12