Configuring Kerberos server
In this recipe, we will configure Kerberos server and look at some of the fundamental components of Kerberos, which are important to understand its working and lay the foundation for setting up Kerberos for Hadoop. Refer to the following diagram, which explains the working of Kerberos:
Kerberos consists of two main components, authentication server (AS) and Key distribution center (KDC, subcomponent KGS). The clients, which could be users, hosts, or services are called principal, authenticate to AS and, on being successful, are granted a ticket (TGT), which is a token to use other services in the respective realm (domain).
The password is never sent over the wire and the TGT granted to the client by the KDC is encapsulated with the client password. The TGT received will be cached by the client and can be used to connect to any service or host within the realm or across domains, if a trust relationship is configured.
KDC is the middleman between clients and services...