Daniel Morante writes on Unibia:
GlusterFS (GFS) is the open source equivalent to Microsoft’s Distributed Filesystem (DFS). It’s a service that replicates the contents of a filesystem in real time from one server to another. Clients connect to any server and changes made to a file will replicate automatically. It’s similar to something like rsync or syncthing, but much more automatic and transparent. A FreeBSD port has been available since v3.4, and (as of this post) is currently at version 8.0 with 9.0 being released soon.
Full disclosure: I never heard of DFS 🤷🏻♂️ When it comes to clustered systems, Microsoft definitely wouldn’t be my first choice. I did however work with AIX GPFS and also with VxFS on multiple platoforms, including Solaris and Linux. There’s also of course cLVM, its implementation on AIX via HACMP and Linux has got something too. I did play with GlusterFS in production for the first time in ~2014 – it was not great. There were many broken parts and some of the things were not really self-contained and relied on userland tools like rsync to be supported and in the right versions. But it did leap forward, eventually stabilized and became, well, to me at least, a golden standard for clustered filesystems on Linux. I’m really happy to see that there is an attempt to get it ported to FreeBSD – it seems to me that it has the potential to combine excellent ZFS baking in this OS with the distributed capabilities as a cherry on top of it.
GlusterFS on FreeBSD is not yet what I would call production quality. There are a few know bugs and performance problems that could ruin your day. The most notable is the fact that GlusterFS uses poll instead of kqueue/kevent. There is also an issue where GlusterFS is (sometimes) unable to correctly find the process ID of the self-heal daemon, causing volume heal commands to fail[…] Other annoyances include the fact that there are still some Linuxisms within the codebase and testing framework. This means GlusterFS might make some Linux specific system calls or look for certain files to be in unexpected locations.
I get it, it’s not there yet, but from the looks of it, it seems that there’s not a lot missing. I’m gonna keep my eye on and fingers crossed for this one 🤞🏻 In the meantime, the linked post is a great introduction not only to GlusterFS, but also to bhyve.