Why does ipconfig show multiple DNS servers?

$ ipconfig /all
DNS Servers . . . . . . . . . . . . : a.b.c.d
                                      a.b.c.e

Why do I have two DNS servers listed? Is it something like try second in case first fails?

Lazer

Posted 2010-09-10T14:33:43.370

Reputation: 13 841

Answers

Yep, exactly correct, redundancy.

Most big DNS providers always give two addresses in the event that one fails.

Google - Configure your network settings to use the IP addresses 8.8.8.8 and 8.8.4.4 as your DNS servers or

OpenDNS - 208.67.222.222 and 208.67.220.220

William Hilsum

Posted 2010-09-10T14:33:43.370

Reputation: 111 572

1+1 - In Windows the terminology is "Primary DNS" and "Backup DNS" – JNK – 2010-09-10T14:37:03.757

2I like the public verizon DNS too, 4.2.2.1 and 4.2.2.2 – JNK – 2010-09-10T14:37:45.473

1@JNK +1, also as a side note, on Windows, if you click the advanced button then the DNS tab, you can have a lot more than two! (I am sure you will be able to do this in other operating systems as well!) – William Hilsum – 2010-09-10T14:38:54.520

1@JNK: 4.2.2.[1-5], and isn't it owned by Level3? – user1686 – 2010-09-10T19:43:10.220

@grawity - it may be now, when I used it before it was a verizon public. – JNK – 2010-09-10T19:58:42.653

Google has a program that they have released that will run speed tests on all of the most popular DNS servers including your ISP's.

http://code.google.com/p/namebench/

This maybe be of some use to you if you wish to tweak your DNS settings.

qroberts

Posted 2010-09-10T14:33:43.370

Reputation: 4 609