Tag: opendns

Cloudflare vs. OpenDNS vs. Google Public DNS

A few months ago, Cloudflare revealed their public DNS server, and I’ve been pleased so far. In addition to performance, Cloudflare claims to be investing heavily in security of DNS. The top competitors in this field already being Cisco’s OpenDNS and Google. As these are all global players, they will (in most cases) have better speed and reliability than those of your local ISP.

Changing these for your entire network generally involves the administrative features/config of your gateway, modem or router. If you are familiar with this, the change should take just a minute or two.

If you are looking for some content filtering at the DNS level, OpenDNS still presents the easiest option for home users and also provides logs.

Cloudflare DNS:
IPv4: 1.1.1.1
IPv4: 1.0.0.1
IPv6: 2606:4700:4700::1111
IPv6: 2606:4700:4700::1001

(Cisco) OpenDNS:
IPv4: 208.67.222.222
IPv4: 208.67.220.220
IPv6: 0000:0000:0000:0000:0000:ffff:d043:dede
IPv6: 0000:0000:0000:0000:0000:ffff:d043:dcdc

Google Public DNS:
IPv4: 8.8.8.8
IPv4: 4.4.4.4
IPv6: 2001:4860:4860::8888
IPv6: 2001:4860:4860::8844

REFERENCES:

IPv6 DNS configuration

As an IT professional, I’ve long been aware of the impending IPv4 exhaustion. To the layperson, this can easily be compared to phone numbers… there are now so many devices connected to the Internet that the size of the number used to identify and reach each of them uniquely is impossible.

IPv6 is a newer addressing system that supports a drastically increased number of addresses/numbers for use. Unfortunately, like Digital TV (in the US), adoption and migration of users and websites is slow.

To do your part as a user, you can change the settings in your gateway/router/modem to allow for IPv6 DNS lookups as most providers already support IPv6 traffic.

You can test your connection here:
http://www.test-ipv6.com/

Here are a few common values, I’ve also provided the Comcast/Xfinity values for reference:

OpenDNS IPv4:

  • 208.67.222.222 (resolver1.opendns.com)
  • 208.67.220.220 (resolver2.opendns.com)
  • 208.67.222.220 (resolver3.opendns.com)
  • 208.67.220.222 (resolver4.opendns.com)

OpenDNS IPv6:

  • 2620:0:ccc::2
  • 2620:0:ccd::2

Google IPv4:

  • 8.8.8.8
  • 8.8.4.4

Google IPv6:

  • 2001:4860:4860::8888
  • 2001:4860:4860::8844

Comcast IPv4:

  • 75.75.75.75
  • 76.76.76.76

Comcast IPv6:

  • 2001:558:feed::1
  • 2001:558:feed::2

REFERENCES:

Private Caching/Relay DNS Server

Since I’ve run a few small websites (like this one) out of my home for years, I’ve found it useful to run a DNS server inside of my firewall. Not only does this make it easier to maintain the websites, but it allows me to lock down security and increase performance of many of my applications.

I run a the following services that use DNS:

  • Apache JAMES – mail server that does lookups to send email and filter inbound SPAM.
  • Analog – web server log analysis.
  • Apache HTTPD – web server, used to host websites, private domains used for internal purposes.

To make things more efficient, I currently have my DNS setup to forward all requests to OpenDNS, allowing for ‘adult’ website filters and analysis of DNS activity.

Some open-source/free DNS servers that I recommend:

Cheers!