To allow users to authenticate to an Azure HDInsight cluster using their on-premises credentials, which solution is valid?

Creating a site-to-site VPN between the virtual network and the on-premises network is a valid solution for allowing users to authenticate to an Azure HDInsight cluster using their on-premises credentials. This setup establishes a secure, encrypted connection between the on-premises environment and Azure, enabling seamless authentication processes.

When users attempt to access the HDInsight cluster, their requests can be routed through this VPN connection, allowing the HDInsight service to communicate securely with the on-premises Active Directory. This facilitates the use of existing on-premises credentials without requiring users to manage separate accounts within Azure. The VPN essentially extends the on-premises network to Azure, making the authentication process smoother and more integrated for end-users.

This method ensures that sensitive data and credentials remain secure while benefiting from the capabilities of Azure HDInsight, ultimately providing a unified experience for the users leveraging the cluster.