kinit:tldr:1222a

The command kinit -p ${principal@REALM} is used to obtain and cache a Kerberos ticket for a specified principal in a specific realm.

Here's how the command can be broken down:

• kinit is the Kerberos command-line utility used to obtain and manage Kerberos tickets. It is short for "Kerberos Initialization".

• The -p option specifies that the following argument is the principal for which a ticket is being requested. A principal is a unique identity associated with an entity (user, service, etc.) in an Kerberos authentication system.

• ${principal@REALM} is a placeholder that should be replaced with the actual principal and realm. The realm is the name of the Kerberos authentication domain.

• The command will attempt to authenticate the principal and obtain a ticket for it. Once authenticated, the ticket is saved in the Kerberos ticket cache on the local machine, allowing the user or process to authenticate against Kerberos-protected services without entering their credentials again.

In summary, the kinit -p ${principal@REALM} command is used to authenticate a principal and obtain a Kerberos ticket for it, which can be used for subsequent authentications within the specified realm.