When making a request to Vault, which type of server does the client communicate with?

When a client makes a request to Vault, it typically communicates with the leader server. The leader server is responsible for processing writes and maintaining the state of the data within the Vault. This ensures that any changes made to the secrets or configuration are managed consistently and accurately.

The leader server coordinates operations such as secret storage, updates, and leases, and it manages the locking mechanisms required to prevent conflicts during these operations. In the event that the leader server becomes unavailable, the system will automatically elect a new leader from the available servers, allowing for high availability and continued operation.

The other types of servers mentioned have distinct roles within Vault's architecture. Replica servers, for instance, are responsible for offering redundancy and scalability by handling read requests and maintaining a copy of the data from the leader server. However, they do not handle writes or updates. Backup servers are typically not involved in active requests and serve as an additional measure for disaster recovery, and there’s no specific role for data servers in the context of Vault’s operation as described in the question.