Has anyone implemented MySQL replication for a mission critical application? I seek opinions of skunks who have "trode" this path, no need to make the same mistake twice. My goal is to make a certain LAMP app be available to offices in 10 different towns even when the network is non-existent. My chosen solution is a master-master replication of the database in all the 10 offices. (This takes care of the network going down). So each office users access the app in hosted in their local network, the app works with the local replica, thus making it "seem" faster. For each office, I am thinking of using DRDB and Heartbeat to have redudant instances of the replicas on standby, in an active/passive configuration. (This creates redudancy in each office). And since budget is non-existent, I will be using normal PCs with a bit more RAM. My primary concern is the master-master replication, will it work in real life as it does in theory especially when the network is unavailable for extendend periods of time?