"Sanoid helps to recover from what I like to call "Humpty Level Events." In other words, it can help you put Humpty Dumpty back together again, on ZFS filesystems."
"Sanoid is open source software, and so are all its dependencies. You can run Sanoid and Syncoid themselves on pretty much anything with ZFS. I developed it and use it on Linux myself, but people are using it (and I support it) on OpenIndiana, FreeBSD, and FreeNAS too."
Sounds like a great utility.
(From the article Avoiding data disasters with Sanoid on opensource.com)