Comment 8 for bug 1391010

Reviewed: https://review.fuel-infra.org/5797
Committed: https://review.fuel-infra.org/gitweb?p=openstack/nova.git;a=commitdiff;h=193735ca11d8d55bb9b581b3ba4bde71f74a2ff9
Submitter: Roman Podoliaka
Branch: openstack-ci/fuel-6.1/2014.2

commit 193735ca11d8d55bb9b581b3ba4bde71f74a2ff9
Author: Timofey Durakov <email address hidden>

Fixed nova-network dhcp-hostsfile update during live-migration

During live migration _post_live_migration and
post_live_migration_at_destination_method are executed
simultaneously, because second one is called over rpc.cast
In _post_live_migration method there was setup_network_on_host
call with teardown=True, which expects new host in instances
table db field. This update could be happened later, as it
executes on destination node in second method. To guarantee
execution order setup_network_on_host call, which cleans
dhcp-hostfile is moved to destination node.

Change-Id: I52bea4db7608abcf73fa781d2c0aaf3eaeb2f468
Closes-Bug: #1391010
Upstream-Bug: #1444497