** Description changed: [Impact] I created several VM instances and checked they are all ACTIVE state after creating vm. Right after checking them, shutdown nova-compute on their host(to test in this case). Then, I tried to evacuate them to the other host. But it is failed with ERROR state. I did some test and analysis. I found two commits below are related.(Please refer to [Others] section) In this context, migration_context is DB field to pass information when migration or evacuation. for [1], This gets host info from migration_context. if migration_context is abnormal or empty, migration would be fail. actually, with only this patch, migration_context is empty. so [2] is needed. I touched self.client.prepare part in rpcapi.py from original patch which is replaced on newer version. because it is related newer functionality, I remained mitaka's function call for this issue. for [2], This moves recreation check code to former if condition. and it calls rebuild_claim to create migration_context when recreate state not only scheduled. I adjusted test code which are pop up from backport process and seems to be needed. Someone want to backport or cherrypick code related to this, they could find it is already exist. Only one patch of them didn’t fix this issue as test said. [Test case] In below env, http://pastebin.ubuntu.com/25337153/ Network configuration is important in this case, because I tested different configuration. but couldn't reproduce it. reproduction test script ( based on juju ) http://pastebin.ubuntu.com/25360805/ [Regression Potential] - Existing ACTIVE VMs or Newly creating VMs are not affected by this code - because these commits are only called when doing migration or - evacuation. If there are ACTIVE VMs and VMs got ERROR state caused by - this issue in one host, and after upgrading pkg, All VMs should not be - affected anything by this upgrading. After trying to evacuate - problematic VM again, ERROR state should be fixed to ACTIVE. I tested - this scenario on simple env, but still need to be considered possibility - in complex, crowded environment. + Existing ACTIVE instances or newly creating instances are not affected + by this code because these commits are only called when doing migration + or evacuation. If there are ACTIVE instances and instances with ERROR + state caused by this issue in one host, upgrading to have this fix will + not affect any existing instances. After upgrading to have this fix and + trying to evacuate problematic instance again, ERROR state should be + fixed to ACTIVE. I tested this scenario on simple env, but still need to + be considered possibility in complex, crowded environment. [Others] In test, I should patch two commits, one from https://bugs.launchpad.net/nova/+bug/1686041 Related Patches. [1] https://github.com/openstack/nova/commit/a5b920a197c70d2ae08a1e1335d979857f923b4f [2] https://github.com/openstack/nova/commit/0f2d87416eff1e96c0fbf0f4b08bf6b6b22246d5 ( backported to newton from below original) - - https://github.com/openstack/nova/commit/a2b0824aca5cb4a2ae579f625327c51ed0414d35 ( + - https://github.com/openstack/nova/commit/a2b0824aca5cb4a2ae579f625327c51ed0414d35 ( original) [Original description] I'm working on the nova-powervm driver for Mitaka and trying to add support for evacuation. The problem I'm hitting is that instance.host is not updated when the compute driver is called to spawn the instance on the destination host. It is still set to the source host. It's not until after the spawn completes that the compute manager updates instance.host to reflect the destination host. The nova-powervm driver uses instance events callback mechanism during plug VIF to determine when Neutron has finished provisioning the network. The instance events code sends the event to instance.host and hence is sending the event to the source host (which is down). This causes the spawn to fail and also causes weirdness when the source host gets the events when it's powered back up. To temporarily work around the problem, I hacked in setting instance.host = CONF.host; instance.save() in the compute driver but that's not a good solution.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1535918 Title: instance.host not updated on evacuation To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-archive/+bug/1535918/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
