nova scheduler doesn't find suitable compute node in time
I recently added more compute nodes to my devstack installation. When I goto create a new instances it fails saying unable to find suitable hosts. If I create that same instance manually specifying the new compute node, it works fine. Are there any nova scheduler changes you can suggest that will help on choosing a suitable node?
I suggest to turn on debug logging in Nova (I think that) and find out which filter is responsible for 'No valid host found'. And maybe remove that filter from nova.conf temporarily just to double check.