Asterisk Failover - 2 Servers 1 PBX

We have two servers and we need to create some sort of fail over for our current asterisk server so if the internet connection (they are both in data centers so we are not worried about power dropping out) should be lost on the main the second box will get asterisk up and running to take calls until the first box returns to service. The second box will need asterisk installed or reconfigured and the current servers config/menu recordings/etc copied over. If possible, we would like this to all be automatic should we make a change to the first box but I do not know if rsync can do this or not.