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Why we have two IPs for dns entry like in Google DNS - 8.8.8.8 8.8.4.4

Or as in OpenDNS - 208.67.222.222 208.67.220.220

Also in router settings, it shows always 2 ips for DNS.

Any specific purpose for the same.

Just curious.

rahijain
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1 Answers1

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Redundancy.

If one fails to respond, the other one will be tried. Everything in computing should be at least N+1.

Tom O'Connor
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  • Yeah that's there. But any relation between them. I mean can i use one from google dns and one from opendns to have better effect ? – rahijain Jan 08 '14 at 10:46
  • You can if you like. OpenDNS does some strange things on NXDomain, and redirects you to their "helper" page sometimes. (or used to..) – Tom O'Connor Jan 08 '14 at 11:03