Load balancing
When an administration site is deployed across multiple instances behind a load balancer, it is crucial that all instances share the same cryptographic keys. Without a consistent key store, users might experience failed authentications or session inconsistencies because each server could potentially use different keys to encrypt and decrypt data. Persisting these keys in a centralized location ensures that every instance of the administration site can access the necessary keys to operate seamlessly.
Using a Shared Directory for Cryptographic Keys
The current best practice involves storing the cryptographic keys in a shared directory that is accessible to all instances of the administration site. This approach not only simplifies key management but also guarantees consistency across servers. By persisting the keys in a single, common location, the risk of key mismatch is minimized, and overall system reliability is enhanced.
A practical way to achieve this in a .NET environment is to edit the Program.cs file of your application.
The key step involves calling the PersistDataprotection method from the fluent API provided by your development framework. This method takes as its parameter the path to the shared directory where the keys will be stored.
Here’s a simple example of how you might implement this in C#:
adminBuilder.PersistDataprotection("C:\");
In this code snippet, the PersistDataprotection method is invoked with the DataProtectionPath property, ensuring that the cryptographic keys are stored in a location accessible to all instances of the administration site.