If you only need 20 Gb/s, you might be able to meet your needs without an exotic distributed filesystem by just getting a single giant server with a rack full o

If you only need 20 Gb/s, you might be able to meet your needs without an exotic distributed filesystem by just getting a single giant server with a rack full of JBODs: Something like this [1] gets you 44 disks in 4u. You can probably fit 9 of those and a server with enough HBAs to interface with it in a 42U rack. 9x44x20TB = not quite 8 PB. Adjust for redundancy and/or larger drives. If you go with SAS drives, you can have two servers connected to the drives, with failover. Or you can setup two of these racks in different locations and mirror the data (somehow). [1] https://www.supermicro.com/en/products/chassis/4U/847/SC847E1C-R1K23JBOD https://www.supermicro.com/en/products/chassis/4U/847/SC847E... (as an illustration, sas jbods aka disk shelves are widely available from server vendors)