App Engine is also a good way to do this. Let's say you have the bulk of your site running on AWS (assume for whatever reason you don't want to use GAE as your

App Engine is also a good way to do this. Let's say you have the bulk of your site running on AWS (assume for whatever reason you don't want to use GAE as your primary environment) * Have a heartbeat task on GAE that polls your server, and if its running, write to "serverisrunning" on memcache with a short time to live. * (normal operation) : redirect initial visitors to your AWS site. * (server not responding to a heartbeat task on GAE, or memcache miss), serve static content from GAE, or a limited functionality version of your app hosting on GAE (for example, a static site with signup form). This type of setup has the added bonus of automatically detecting an outage and responding to it. While App Engine has its own downtime issues, outages are transient. Since they migrated to the high replication data store, I haven't seen anything that lasted more than a few minutes.