I've inherited a legacy rails application that I recently moved wholesale to AWS. Part of the infrastructure is a ferret index that exists on each of the ten backend application servers that build subscriber email every night. We have a large database, so it takes about four hours for each of the backend servers to rebuild the index every day. Across ten app servers, that's a lot of extra hours to keep most of them spun up when they would otherwise be spun down. (all told, each set of indices is about 8gb per server).
All the rebuilt ferret indices are reading the same data from the main database. What I'm wondering is - could I have one applications server do the daily rebuild, then rsync the final rebuilt indices to the other application servers? I don't know enough about ferret (or rails for that matter) to know what sorts of dependencies there might be here. I would think that an index is an index, so copying the exact same data to all the servers should be 'noncontroversial' so to speak. Am I out in the weeds or on the right track?