GlusterFS description sounds very promising: easy configurable, fault tolerant distributed file system. It promises petabytes of storage on a single name space on a commodity hardware.
It implements mirroring and stripe modes which makes it possible to store big files over a set of smaller storage servers.
The question is how easy the system can be extended and how easy faulty or just old elements can be removed from the system.
Is it a downtime involved in those operations?
Are there any alternatives in Open Source or any other world?
It seems that GlusterFS can be extended but a downtime is involved.
There is no stright forward solution to remove old or obsolete chunks from GlusterFS.