Rules for traffic exceeding QPS limits ====================================== Traffic that exceeds a QPS limit, in total or per IP (subnet) can be matched by the :func:`MaxQPSIPRule`-rule. For example: .. code-block:: lua addAction(MaxQPSIPRule(5, 32, 48), DelayAction(100)) This measures traffic per IPv4 address and per /48 of IPv6, and if UDP traffic for such an address (range) exceeds 5 :term:`qps`, it gets delayed by 100ms. As another example: .. code-block:: lua addAction(MaxQPSIPRule(5), SetNoRecurseAction()) This strips the Recursion Desired (RD) bit from any traffic per IPv4 or IPv6 /64 that exceeds 5 qps. This means any those traffic bins is allowed to make a recursor do 'work' for only 5 qps. If this is not enough, try: .. code-block:: lua addAction(MaxQPSIPRule(5), DropAction()) -- or addAction(MaxQPSIPRule(5), TCAction()) This will respectively drop traffic exceeding that 5 QPS limit per IP or range, or return it with TC=1, forcing clients to fall back to TCP. To turn this per IP or range limit into a global limit, use ``NotRule(MaxQPSRule(5000))`` instead of :func:`MaxQPSIPRule`.