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In the past I was always told by colleagues 4.2.2.2 appears to work faster and have to combine that with Google's public DNS*. Using 8.8.8.8 as primary and 4.2.2.2 as secondary. However, Google only provides 8.8.8.8 and 8.8.4.4, so who provides 4.2.2.2? And if true, why is 4.2.2.2 faster?

*Note: These IP addresses are used to dig domains and to determine if local DNS changes has propagated over all over the internet.

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    nslookup 4.2.2.2 = "b.resolvers.level3.net" Jan 29, 2014 at 18:32
  • 1
    Makes me wonder why 1.1.1.1 and 2.2.2.2 etc aren't used.
    – Roger Far
    Jan 29, 2014 at 23:52
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    1.1.1.1 is unofficially reserved (allocated to "Debogon-prefix") — it receives a ton of bogus traffic from misconfigured devices, so it's unusable in practice.
    – user89623
    Jan 30, 2014 at 0:17
  • Microsoft uses internetbeacon.msedge.net => 13.107.4.52 for its Powershell module Test-NetConnection. Feb 2, 2017 at 15:21
  • @duskwuff-inactive- Surprise ;)
    – user398328
    Apr 6, 2020 at 23:54

1 Answer 1

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4.2.2.2 is one of six (4.2.2.1 through 4.2.2.6) DNS servers run by Level 3 Communications, a Tier 1 ISP. These are supposed to be used by Level 3 customers only, although they have gone into general use over the years. Supposedly, they are officially discouraging people from using these DNS servers, as they are under no obligation to provide this service and can theoretically discontinue them at any time (whereas Google provides their DNS servers expressly for public use).

More information here.

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    4.2.2.2 is also useful for network debugging, namely an easy to remember IP that responds to pings. For years, if there was a network connection issue, the first step would be to ping the router, then to ping 4.2.2.2, to see if packets got on the net (no DNS needed). 8.8.8.8 is a bit easier to remember now though :) Jan 29, 2014 at 18:35
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    BTW, Level 3 are now hijacking some failed requests
    – Sathyajith Bhat
    Jan 29, 2014 at 18:47
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    But yet again, Google isn't under any obligation.
    – oldmud0
    Jan 30, 2014 at 1:42
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    Link to level 3 story, without reddit: james.bertelson.me/blog/2014/01/… Jan 30, 2014 at 7:42
  • @KristofferSall-Storgaard, link doesn't work.
    – Cœur
    Jul 28, 2016 at 3:17

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