Though you can install OpenStack Object Storage for development or testing purposes on one server, a multiple-server installation enables the high availability and redundancy you want in a production distributed object storage system.
To perform a single-node installation for development purposes from source code, use the Swift All In One instructions (Ubuntu) or DevStack (multiple distros). See http://swift.openstack.org/development_saio.html for manual instructions or http://devstack.org for all-in-one including authentication with the Identity Service (keystone).
