Wikipedia
LizardFS
LizardFS is an open source distributed file system that is POSIX-compliant and licensed under GPLv3. It was released in 2013 as fork of MooseFS.
LizardFS is a distributed, scalable and fault-tolerant file system. This is achieved by spreading data over several physical servers and their associated physical drives. This infrastructure is then in turn presented to the end-user as a single logical name space. The file system is designed so that it is possible to add more disks and servers “on the fly”, without the need for any server reboots or shut-downs.