Example configuration

Save this config file somewhere as dnsdist.conf, then run with:

./dnsdist --config /path/to/dnsdist.conf

-- Set the local listening address.
setLocal("127.0.0.1:5300")

newServer({address="8.8.8.8"})
newServer({address="8.8.4.4"})

-- Create a named cache, and bind it to a CDB file that can keep up to 2 million
-- entries in its in-memory cache.
getNamedCache("block"):bindToCDB("/path/to/blacklist.cdb")

-- Define a function that checks the "block" named cache.
--
-- As with any other Lua rule-type function, its lone argument is a DNSQuestion table.
function checkNamedCache(dq)
  local result = getNamedCache("block"):lookupQ(dq)

  for k, v in pairs(result) do
    print(k, v)
  end

  if result.found then
    -- If there is an entry found in the "block" named cache, do not let later rules
    -- process the request, and return an NXDomain response.
    return DNSAction.Nxdomain, ""
  end

  -- There was no match in the named cache; allow rule processing to continue.
  return DNSAction.None, ""
end

--
-- Rules
--
-- Add a rule to call the checkNamedCache function, for each request.
addLuaAction(AllRule(), checkNamedCache)