ITGSS Certified DevOps Engineer Practice Test

What type of certificates are typically used by API clients in Kubernetes?

1. X.509 client certificates

2. Self-signed certificates

3. SSL certificates

4. Service account tokens

The correct answer is: X.509 client certificates

API clients in Kubernetes typically use X.509 client certificates for authentication. X.509 is a standard that defines the format of public key certificates. In a Kubernetes environment, these certificates help to establish secure connections between clients and the Kubernetes API server. When a client connects to the API server, the server can verify the client's identity using the certificate, which contains a public key along with information about the identity of the certificate holder. This method provides a robust mechanism for authenticating clients, as it uses cryptographic signatures to ensure that the certificate provided is valid and has not been tampered with. Other options, while related to security, do not serve the same specific purpose in Kubernetes API authentication. For instance, self-signed certificates can be used in some cases but are typically not recommended for production use due to potential trust issues. SSL certificates refer to security protocols used for encrypting traffic but do not specifically address client authentication. Service account tokens are another form of authentication in Kubernetes, but they are used primarily for accessing the API on behalf of a service account rather than by external API clients. Therefore, X.509 client certificates stand out as the standard method for authenticating API clients in this context.