Draytek Vigor2860 series User Manual page 209

Item
Enable
Server IP Address
Destination Port
Shared Secret
Confirm Shared Secret
After finished the above settings, click OK button to save the settings.
Vigor2860 Series User's Guide
Description
Check to enable TACACS+ feature.
Enter the IP address of TACACS+ server.
The UDP port number that the TACACS+ server is using.
The TACACS+ server and client share a secret that is used to
authenticate the messages sent between them. Both sides
must be configured to use the same shared secret.
Re-type the Shared Secret for confirmation.
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