We create a zero filled file for use as a loopback device for the Swift storage backend. Here we use the disk copy command to create a file named swift-disk and allocate a million 1KiB blocks (976.56 MiB) to it. So we have a loopback disk of approximately 1GiB. We can increase this size by modifying the seek value.
sudo dd if=/dev/zero of=/srv/swift-disk bs=1024 count=0 seek=1000000
