Update: as of Ocata, when using the FilterScheduler, I think the only remaining workaround for BFV with volumes > compute host local disk size is to create and use separate flavors configured for root_gb=0 when booting from volume.
Prior to Ocata, when using the FilterScheduler, an additional workaround was to remove DiskFilter from the configurable enabled scheduler filters.
Update: as of Ocata, when using the FilterScheduler, I think the only remaining workaround for BFV with volumes > compute host local disk size is to create and use separate flavors configured for root_gb=0 when booting from volume.
Prior to Ocata, when using the FilterScheduler, an additional workaround was to remove DiskFilter from the configurable enabled scheduler filters.