The Zumastor Linux storage project adds enterprise storage features to Linux, primarily improved snapshots and remote replication. Point-in-time, near zero-cost, block level snapshots can be added to any existing filesystem and performance does not degrade with multiple snapshots. Remote replication is achieved by sending minimal block level deltas between snapshots without having to traverse the entire filesystem like rsync does.
Chiron FS is a FUSE based filesystem that implements replication at the filesystem level like RAID 1 does at the device level. The replicated filesystem may be of any kind you want; the only requisite is that you mount it. There is no need for special configuration files; the setup is as simple as one mount command (or one line in fstab).
AnomicFTPD is an RFC959-compliant FTP server with OS- independent user and group management. Active and passive modes, non-root mode, and anonymous and/or read-only modes are supported. A built-in client IP filter acts as a firewall and provides additional access limitation. The server has no online interface; attributes, groups, and user accounts are configured through text files. The protocol/ format-unspecified LIST command produces output that is compatible with most FTP clients, including common Web browsers in FTP mode.
Radiant Data PeerFS is real-time peer-to-peer distributed replicating file system featuring global file and sectional locks. All read operations are performed locally, and only file changes are transmitted across the network. It supports databases such as MySQL, as well as images and documents. All nodes are active/active, allowing for load balancing. Clients can also be hot switched between nodes, eliminating downtime. It also supports AES encryption for use across the Internet.