DNS OPcodes (operation codes) are commands given to the DNS server that tell it to do some action, such as a query (Query), an inverse query (IQuery), or a server status request (STATUS). They opSerate on items such as registers, values in memory, values stored on the stack, I/O ports, and the bus. You can add, delete, or modify rules in the default ruleset. You can allow, deny, drop, or block specified DNS OPcodes.
If you use Active Directory and your Active Directory configuration requires dynamic updates, you must allow DNS OPcodes in your DNS-Incoming proxy action rules. This is a security risk, but can be necessary for Active Directory to operate correctly.
For more information on the integer values of DNS OPcodes, see RFC 1035.
If you modified a predefined proxy action, when you save the changes you are prompted to clone (copy) your settings to a new action.
For more information on predefined proxy actions, see About Proxy Actions.