When there is a failure in nova snapshot before uploading the image to glance (for example failure on hypervisor capturing the disk image as a file) there is no way to notify glance that this image is in error state nor the is a way to set it to kill. This will result on uncertainty from a client side checking image state, image state will be in queue until the call from nova to upload which will then go to saving and the active or killed depending on the success of upload to store. If an error occurs before image upload request, nova cannot call update with image to upload and image will stay in queue state. Client will not be able to determine if this is a long running snapshot or something bad has happened.
One suggestion could be to add a new known property named error to the update request. If api sees this it will then set the image to error and add the error to image metadata. I will try a couple of things here, but wanted to get other folks to pitch in on possible solutions.
Capturing an irc log
dperaza: hello all, I just added this bug report, will like to get feedback from folks that have more experience. I could be missing something: https:/
[1:10pm] markwash: dperaza: Hi
[1:10pm] markwash: dperaza: you've hit on one of our top pain points with nova and glance
[1:10pm] markwash: and its got a bit of a history
[1:11pm] markwash: dperaza: from glance's perspective, a failed upload should put the image back into the "queued" or "pending" state
[1:12pm] markwash: dperaza: more satisfying solutions are going to have to involve greater orchestration from nova