In article <Pine.SOL.4.30.0202242244400.13803-100000 at mion.elka.pw.edu.pl>, Marek Iwanejko <M.Iwanejko at elka.pw.edu.pl> wrote; } 1) 2-3 Heavy machines (let's say 4 CPU, 12GB RAM) as reader server(s) } with disk arrays. One server is master, rest are slave. } It's expensive, but full redundant, nice to maitenace.