Copy ferret index to other servers?
I don't see why not.
I mean, have you tried it?
Ferret is just a ruby port of Lucene, and you can do neat things with a Lucene index, like rsync, and NFS share it, as long as the servers only need Read-Only access to it.
You will however, have to stop indexing in order to run the copy process, so that you get a consistent snapshot of the data in the index.
Although it sounds like it's a batch job that runs for a bit and stops, ICBW.
My best suggestion to you is to try it. Take a couple of servers out of the pool, and experiment with rsyncing the index between them, then test it. You should be able to define some test cases for validating your hypothesis, right?
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