How to best utilize hardware resources in an WCF application?

Question

One of my application, which is a service application developed using WCF, is being production released. It uses a SQL Server express internally.

Since the service will play an important role and has to be up 24x7, I planned to deploy 2 machines:

• One machine will be operational and serve the requests. It will also hold the SQL Server database. A scheduled task will take its backup daily.
• Second machine will have service application deployed and configured with an empty database. It will be ready to be turned on.

If in any case, first machine goes down, my plan is to restore the last database backup to second machine and turn it on. Sort of like cold backup machine.

I have following questions in mind:

1. Seems like I am wasting a machine which will be idle for most of its life time. Can I use it to share some load in addition to use it as cold backup machine.
2. Are there better ways to manage this situation? For example, second machine acts automatically when first one fails. Sort of like hot backup!

Answer 1

Thoughts:

Well, in your scenario, what happens if your core machine dies? It's database is lost as well. So you bring up your second one with no data!

My suggestion:

You need to have it such that the DBs are mirrored, and then you will need a central server that sends requests to either one (load-balanced style).

If one dies, you are left with the other taking the entire load. At the time you notice the death of one, you attempt to restore it as best you can.