This is 'cache', my OpenWRT router has this for thousands of records, but negative cache means: "remember this domain doesn't exist and don't retry asking other

This is 'cache', my OpenWRT router has this for thousands of records, but negative cache means: "remember this domain doesn't exist and don't retry asking other DNS providers". This is very dangerous. Your browser AND operating system AND router already provide DNS caching, it's not something average user should even think about. You might want to consider it when things in your ISP go wrong (hello BT), or majority of computer request the same domains frequently, but then again, your router should do it already.