[ww520]

CopyCat looks really good for HA and fault-tolerance. Not so sure about its scalability since all writes go through the single leader node. It's more appropriate for the use of maintaining metadata of a distributed system, rather than maintaining the data themselves.

For your requirement, can you use S3 or something similar?

[mavelikara]

Thanks! The software I am writing needs to be (easily) installed at the customer site. So, S3 won't work for me. Are there any open source S3 clones that are easy to setup?

[michaelmior]

If you mean that you need something that supports the S3 API, you could try S3Proxy[0]. It basically presents the S3 API over a variety of different storage backends.

[0] https://github.com/andrewgaul/s3proxy

[bochi]

Riak CS is S3 compatible.

I have a very similar problem and end up writing a python script that copies the files to cassandra and Nginx + Lua to serve them using lua-resty-cassandra. The read/write throughput is still not as good as I was expecting though.

[stonith]

You could try OpenStack's Swift project.

[SEJeff]

That is a "design feature" of raft, which allows it to lack the unbelievable complexity of Paxos, Multi-Paxos, or something like ZAB (yet another paxos variant).