If you are looking into shared storage, you need to look into SAN solutions. Network storage that is used over standard networks is NOT suitable for video production needs. They have different requirements. Video needs a constant HIGH data transfer rate, and typical networks that just transfer data don't work that way. They typically send data in small bursts or packets. Only specially designed Video networks. Shared Area Storage (SAS) or Shared Area network (SAN) designed to handle video will work.
And sorry but, they ain't cheap.
XSAN, MetaSan, SanMP, EditShare...
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