dnsdist: support several dynBlockRules of the same type with different actions

[rgacogne]

• Program: dnsdist
• Issue type: Feature request

Short description

It would be very useful to be able to insert more than one dynBlockRule of the same type (Query rate, rcode rate, response byte rate...) but with different thresholds and actions.

Usecase

That would allow generating an alert without blocking any query over a certain threshold, while blocking over a different one.

Description

local dbr = dynBlockRulesGroup()
dbr:setQueryRate(50, 10, "Exceeded query rate", 60, DNSAction.NoOp)
dbr:setQueryRate(100, 10, "Exceeded query rate", 60, DNSAction.Drop)