title: Kerberos authentication fails, "Configuration file does not specify default realm"
body: <p>I am attempting to set up Kerberos authentication with Freeradius. At the moment when I run radtest the authentication fails and I get the following error in my logs</p>
  
  <pre><code>(0) Login incorrect (krb5: Failed parsing username as principal: Configuration file does not specify default realm): [user/Password123] (from client localhost port 1812)
  </code></pre>
  
  <p>In my krb5 configuration file I have specified a service principal so I am unsure why I am getting this error. Here is a snippet for context (sensitive values modified)</p>
  
  <pre><code>krb5 {
          #
          #  The keytab file MUST be owned by the UID/GID used by the server.
          #  The keytab file MUST be writable by the server.
          #  The keytab file MUST NOT be readable by other users on the system.
          #  The keytab file MUST exist before the server is started.
          #
          keytab = /etc/raddb/mykeytab.keytab
          service_principal = http/princ@example.com
  </code></pre>
  
  <p>Is there anything wrong with this configuration? Or am I looking in the wrong place?</p>