41452a5c6a
When an instance with attached volumes fails to spawn, cleanup code within the compute manager (_shutdown_instance called from _build_resources) will delete the volume attachments referenced by the bdms in Cinder. As a result we should check and if necessary recreate these volume attachments when rescheduling an instance. Note that there are a few different ways to fix this bug by making changes to the compute manager code, either by not deleting the volume attachment on failure before rescheduling [1] or by performing the get/create check during each build after the reschedule [2]. The problem with *not* cleaning up the attachments is if we don't reschedule, then we've left orphaned "reserved" volumes in Cinder (or we have to add special logic to tell compute when to cleanup attachments). The problem with checking the existence of the attachment on every new host we build on is that we'd be needlessly checking that for initial creates even if we don't ever need to reschedule, unless again we have special logic against that (like checking to see if we've rescheduled at all). Also, in either case that involves changes to the compute means that older computes might not have the fix. So ultimately it seems that the best way to handle this is: 1. Only deal with this on reschedules. 2. Let the cell conductor orchestrate it since it's already dealing with the reschedule. Then the compute logic doesn't need to change. [1] https://review.openstack.org/#/c/587071/3/nova/compute/manager.py@1631 [2] https://review.openstack.org/#/c/587071/4/nova/compute/manager.py@1667 Change-Id: I739c06bd02336bf720cddacb21f48e7857378487 Closes-bug: #1784353 |
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| .. | ||
| tasks | ||
| __init__.py | ||
| api.py | ||
| manager.py | ||
| rpcapi.py | ||