PackStack installs Block Storage that uses a volume group. When the Block Storage service starts, it looks for a specific volume group named cinder-volumes, the volume that PackStack can create should only be considered an example storage volume for testing. It is placed in /var/lib/cinder and installed as a loopback storage device on the host that the Block Storage service is running on. To avoid the creation of loopback devices, you have to create volume groups manually for the Block Storage service before installing and deploying OpenStack using PackStack.

# pvcreate /dev/sdX
# vgcreate cinder-volumes /dev/sdX

PackStack does not install a volume for Object Storage, instead it adds a device to an Object Storage ringfile. On the Object Storage host this is then represented by a directory in /srv/. Ideally the directory for the Object Storage device should be a separate file system. If you don't have one and just want to test Object Storage, then PackStack can create a small loopback storage device in place of a separate partition.

You can manually set CONFIG_SWIFT_STORAGE_HOSTS=192.0.43.10/sdb1,192.0.43.10/sdc1. This would set up Object Storage with /dev/sdb1, /dev/sdc1 and no testing loopback device.