I am currently providing some web applications to my customers (apache/php/mysql on Windows server). I'm looking to provide some sort of fail-over server in the case my server has a hardware failure. My server is running in a data center.
I think I will just add a second server that is installed in the same rack. My 1st server will act as a spare server and I will add extra NICs to create a local network between the two servers. I will use mysql replication and something like rsync to synchronize all web applications continuously. Then I will set up some monitoring on the spare server so when my main server doesn't respond the spare server will change it's ip address to match the main one. (maybe a manual change instead of automatic).
My question is: Will changing the ip address make the transition almost instantly? Or will the router/switch in the data center not detect the change quickly enough (because of ARP caching). Do I also need to clone the MAC address in such a situation?