This configuration parameter sets the maximum size packet that the Kerberos libraries will attempt to send over a UDP connection before retrying with TCP. If the packet size is larger than this value, only TCP will be tried. If the value is set to 1, TCP will always be used. The hard UDP limit is 32700. Values larger than this are ignored and the UDP hard limit is enforced.

This key only takes effect if krb5.forcetcp is set to false.

If krb5.forcetcp is true, and the agent is managing the krb5.conf file, it will set udp_preference_limit = 1, so that the Kerberos libraries will always use TCP.

In most cases, you set this configuration parameter using group policy to set a specific value.

You can, however, set it manually in the configuration file if you are not using group policy or want to temporarily override group policy.

If this parameter is not defined in the configuration file, the default value is 1465; for example: