The Kerberos client supports both TCP and UDP protocols for communicating with the KDC. By default, the session attempts to communicate using UDP. However, if the packet size exceeds the value specified for the, the session switches to TCP (which may require more time to initiate a connection).
If you are having problems authenticating to a Windows KDC and you belong to a large number of groups, or ifis selected, decreasing the value for may help. Alternatively, try increasing the setting for the .
To change the maximum UDP packet size
Start Kerberos Manager.
From themenu, choose .
From thetab, select a realm from the , and then click .
On the KDC tab, specify a value for. To use only TCP communications, set this value to 0.