Introduction
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Want to change your DNS server?
There are three sections in this how to guide.
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For speedy performance
Every web page requires an IP address before it can be loaded. The time taken to resolve a DNS name can add several seconds to the loading of a page. The faster your DNS server then the quicker your pages will load.
The larger the database of the DNS server then the greater the likelihood that the name will be found without searching on other DNS servers. These cached hits are much faster than uncached hits. Typically by a factor of ten so a 0.1 second.cached name could take 1 second if it is not found in the DNS server database.
For increased reliabilty
Most DNS servers are available near enough to 100% of the time. If your isn't then find a more reliable server. DNS queries can timeout or, in the worst case, receive no response at all. There are several ways to reduce such problems:
For greater safety
All DNS servers do not offer the same features or have the same vulnerabilities. Many DNS servers still do not operate using established security features like DNSSEC.
Some DNS servers provide additional features such as the filtering of web addresses to improve security. These solutions can create other problems.:
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Configuration
Automatic configuration from your ISP?
You will usually define your DNS servers when you configure your Internet network connection whether dial-up or broadband. Most Internet Service Providers (ISPs) have automatic configuration of some sort so the DNS servers are defined automatically. If you had to manually configure the network connection then chances are that you also had to manually define the DNS servers.
Configuration on your system
DNS servers settings will exist for each PC you use on the Internet whether they were manually input or automatically configured. The key question is where are my external DNS servers defined?
How to find your system DNS servers
There are several methods to find your system DNS servers. If you want to know more then go to the next section Changing your DNS configuration for further resources.
Example of method 2 - Inspect your network connection settings in Windows
Note that you can exit out of this by pressing the Esc key, selecting Cancel, or closing each window.
How to test if the system DNS configuration is damaged
You can incorrectly configure your system DNS by, for example, typing in incorrect IP addresses for the DNS servers. If you do this then your web browser will not be able to access Internet resources using domain names but you should be able to use URLs with a valid IP address. Just type a valid IP address in as the URL and your browser should add the rest e.g. 72.52.134.16 is converted to http://72.52.134.16/.
If you find you have lost all web access even using IP addresses then that is very unlikely to be a DNS problem. Your network connection could be down or malware could have changed your configuration (e.g. by setting your network connection to use a proxy server).
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Before configuring your chosen DNS Servers
You might want to run a DNS Spoof Test to check the vulnerability of your chosen DNS servers. Just be aware that some routers lockup or crash if you run these tests. GRC provides a list of routers with known problems. It didn't include mine which crashed when I tested it. I had guessed it might because it is similar to some of those listed. That's a good reason to get a better router. See GRC's notes at the bottom of the DNS Spoof Test page for a list of routers that fail in this way.
Resources to help you change your DNS configuration
There are programs to automate the changeover to better DNS servers but I'd give them all a miss. Instead, I encourage you to visit some excellent resources that will help you.
Web quides and tutorials
If you are at all unsure, you should have a look at these resources about configuring your DNS servers. Just remember that the DNS server IP addresses they show you in the guides are for their servers. You can substitute the IP addresses for your preferred DNS servers.
Software that might help you to change your configuration but are too limited
DNS Jumper will change your DNS addresses for you but has some significant weaknesses:
DNS Helper (formerly Google DNS Helper) is a utility to change to one of the main global DNS service providers that I do not recommend:
Likewise Public DNS Server Tool is too limited to be recommended.
After you change your DNS configuration
Flush the system DNS caches
When you change your DNS configuration you should clear the system caches so that the new DNS settings take immediate effect. I use CCleaner, the Editor's Choice for Best Free File Cleaner, to clear the caches because it runs once and cleans each browser's cache. Other options are more limited.
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