If you’ve spent 2017 being periodically plagued by your ISP’s flaky DNS server, IBM Security has a fast free-and-public DNS lookup server called Quad9 at the 9.9.9.9 address. It was introduced in November, but many will have been so busy in the weeks before Christmas that the news passed them by. It’s very easy to apply, and once in use it filters out the addresses of botnets, phishing scams and the like. As well as your desktop PC, it can also be applied to your various devices and even to your router.

IBM state that Quad9 is “engineered to not store, correlate or otherwise leverage any personally identifiable information (PII) from its users.” It’s been set up as a non-profit and it passes the sniff-test among the sceptical techies at The Register, who usefully note that Quad9 also has a free IPv6 DNS server at 2620:fe::fe


Update: Regrettably it completely shuts down your DNS access if you try to run legitimate link-checking software such as Linkbot. Presumably the system flags you as a botnet if you try to run Web automation software of that type. Oh well. Which means Quad9 has been uninstalled here. Though if you don’t check the links on your websites frequently, then it may be useful to you. It can also be useful as an emergency fall-back, and the 9.9.9.9 address is easy to remember. Google has a similar product at 8.8.8.8