[scottbruin]

To add more, as well: we use HAProxy for deploying (tell it to take down nodes using the unix socket), we have it set up to meter requests to a machine just brought back online, and with one command we can route all traffic to a standby Apache instance that serves a maintenance page. On top of that it has the monitoring page, and using the socket we pull stats every minute and ship them off to Librato Metrics as well as watch for high sessions and the like. I (obviously) cannot sing its praises enough.