With Azure auto-scaling do I need to specify a MachineKey in web.config?

Question

For a ASP.NET MVC project I worked on recently it was deployed to multiple server instances and required to have a machinekey configured.

I have another project which will be deployed onto Azure (Web site standard) and I'm not sure if Azure configures a machinekey for you or handles that kind of thing internally itself or if you have to configure one.

Does anyone know. I can't seem to find any resources specifically about this.

Answer 1

Azure will automatically set the same machinekey for all instances of a WebRole so you don't need to explicitly set it. However, if you delete and redeploy or do a VIP swap then the machinekey will change which could cause problems with existing clients so you should set a machinekey for this scenario.