Zentyal (formerly eBox Platform) is a small business server that offers small and medium businesses an affordable and easy-to-use enterprise-level computer network. It can act as a Gateway, Infrastructure Manager, Unified Threat Manager, Office Server, Unified Communication Server, or a combination of these.
zrep provides an easy-to-use program to manage zfs filesystem replication and failover. No configuration files are required. The program is developed under Solaris, but may work with any up to date zfs implementation. The executable is a single script. Initialization does a full data copy, but subsequent syncs are incrementals. It uses internal locking to make sure there is no danger of overlap if you just shove it in cron to run every minute. Design target is more "near-time replication", since the sync can be run every minute or more. However, it could conceivably be used for "backup" purposes as well.