On Tue, Jun 28, 2016 at 9:42 AM, Andreas Scheuring <scheu...@linux.vnet.ibm.com> wrote: > I'm currently working on solving Nova-Neutron issues during Live > Migration. This mail is intended to raise awareness cross project and > get things kicked off.
Thanks for sending this. > The issues > ========== > > #1 When portbinding fails, instance is migrated but stuck in error state > #2 Macvtap agent live Migration when source and target use different > physical_interface_mapping [3]. Either the migration fails (good case) > or it would place the instance on a wrong network (worst case) > #3 (more a feature): Migration cross l2 agent not possible (e.g. > migrate from lb host to ovs host, or from ovs-hybrid to new ovsfirewall > host) Since all of these issues are experienced when using live migration, a Nova feature, I was interested in finding out how Nova prioritizes getting a fix and then trying to align Neutron's priority to that priority. It would seem artificial to me to drive priority from Neutron. That's why I mentioned it. Since Nova is hitting a freeze for non-priority work tomorrow, I don't think anything can be done for Newton. However, there is a lot of time to tee up this conversation for Ocata if we get on it. > The proposal > ============ > All those problems could be solved with the same approach . The proposal > is, to bind a port to the source AND to the target port during > migration. > > * Neutron would need to allow multiple bindings for a compute port and > externalize that via API. > - Neutron Spec [1] > - Bug [4] is a prereq to the spec. > > * Nova would need to use those new APIs to check in pre_live_migration, > if the binding for target host is valid and to modify the instance > definition (e.g. domain.xml) during migration. > - Nova Spec [2] > > This would solve the issues in the following way: > #1 would abort the migration before it started, so instance is still > usable > #2 Migration is possible with all configurations > #3 would allow such a migration > > Coordination > ============ > Some coordination between Nova & Neutron is required. Along todays Nova > Live Migration Meeting [5] this will happen on the Nova midcycle. I put > an item on the agenda [6]. I'll be there. > Would be great that anybody that is interested in this bugfix/feature > could comment on the specs [1] or [2] to get as much feedback as > possible before the nova midcycle in July! > > Thank you! > > [1] Neutron spec: https://review.openstack.org/#/c/309416 > [2] Nova spec: https://review.openstack.org/301090 > [3] macvtap bug: https://bugs.launchpad.net/neutron/+bug/1550400 > [4] https://bugs.launchpad.net/neutron/+bug/1367391 > [5] > http://eavesdrop.openstack.org/meetings/nova_live_migration/2016/nova_live_migration.2016-06-28-14.00.log.html > > [6] https://etherpad.openstack.org/p/nova-newton-midcycle __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
