Manage different configurations on different servers

We are using Grails to develop and deploy on 4 servers. Each server uses the same application but loads specific configuration such as a camel route configuration or a quartz configuration. We use server IP to distinguish different xml configuration such as:

if (IP == '10.25.3.3') {
   import resource1.xml
} else if (IP == '10.25.3.4') {
   import resource2.xml
}

But as deploying on more servers or adding more configurations, we need to add more conditions or change the above code when the server IP changes. I think there may be a better way to manage these configurations. So I want to ask is there any recommended way to manage these configurations and load the configuration on different environments?