Alex, Drew from ChooseLinux, and Brent (of the Brunch fame) sit down with Antonio Musumeci, the developer of mergerfs during the JB sprint. It is a union filesystem geared towards simplifying storage and management of files across numerous commodity storage devices, it is similar to mhddfs, unionfs, and aufs.
mergerfs makes JBOD (Just a Bunch Of Drives) appear like an ‘array’ of drives. mergerfs transparently translates read/write commands to the underlying drives from a single mount point, such as /mnt/storage. Point all your applications at /mnt/storage and forget about how the underlying storage is architected, mergerfs handles the rest transparently. Multiple mismatched size drives? No problem.