At my workplace, we (used to) use GlusterFS as our NFS between various servers. It stored uploaded user files, various versions of our assets, etc. GlusterFS has had a love-hate relationship in our company. When it works, its fine. When it doesn't, it does so horribly (we have lost data and had to figure out ways to recover it). There has also been version incompatibility issues so that means upgrading our infrastructure to new versions was avoided. Until March of this year when Ubuntu 14.04 was no longer going to be supported; we needed to upgrade those servers.