I currently run spiderloop.com a SEO control panel designed for windows hosting accounts. The site and web service is hosted on our own server and works great, however I am concerned about redundancy and do not want to purchase a whole other server just to be fail safe. So I am going to purchase a shared hosting account to facilitate redundancy.
So here is the question.
How do I do it? How do I set up my current host to redirect to the new host when it goes down?
If the current host has problems how can I force the users browser to redirect to the redundant host? I simply don't understand. Can somebody enlighten me?
The only way, and its not a good one, is to use some sort of DNS solution. Those that advise this type of solution will tell you to set the server's A record with a low TTL (a few seconds) and when site goes down, change the A record to backup server. (or subscribe to a service that will monitor web and do this for you automatically)
I do not recommend this solution. The problem here is that many dns caching servers and clients ignore TTL. An additional server with load balancing is the best fault tolerant system for you.
Hm. If you need real time redundant I think you have to got another server that calls "mirroring", for the dns thing mentioned above, you have to wait around 1 hour propagation to ensure it works right everywhere.
You'd probably need to setup some sort of router / NLB which all traffic is routed via and then the router intelligently choses which IP to send the requests too. You'd probably want redundant routers too! I'd say if you're looking for shared hosting as a failover that the cost / risk involved doesn't warrant a seamless solution.