solr have its replication way and it use rsync transport.
i try it but not success maybe because i m poor in freebsd.(if u know how to config and use, tell me and i will be very happy.:) ) when i use mysql replication, i think why not use it? master: mysql (innodb or isam), slave: mysql(isam), master---->slave with replication. we just write program in slave to read the data which solrflag is 0 and index it. User can seach through slave's index data. if more solr's server, maybe use slave group. master 1 ----> slave 1 master 2 ---> slave 2 ..... master n ---> slave n i only test one master-> one slave it can help we use multi platform.. maybe it have wrong or not fits for thousands searching let me know what u think. -- regards jl