> Each "fault-tolerance" criteria added adds some cost. At some point the cost of being resistant to errors exceeds the cost of downtime. Agreed, but the cost/

> Each "fault-tolerance" criteria added adds some cost. At some point the cost of being resistant to errors exceeds the cost of downtime. Agreed, but the cost/benefit should be the same at every level in the stack. I get it when people build a single-server system. I'm just baffled that so many people insist they need a load balancer and multiple instances of their application so that there's no single point of failure (which is not free by any means), but then run them all off of a single SQL server.