You probably found or have been pointed to this article because you are having issues pulling up your website or accessing your email and were told it may have something to do with non conforming DNS servers. You will want to update the DNS settings used by your computer to servers that conform to Internet standards. This will ensure that your requests for sites are being served up by the correct servers as dictated by the hosting ISP.
For a longer explination of the issue, please scroll to the bottom of this article.
So now that you have an overview of the issue, what can you do to solve it? The best way to solve an immediate DNS issue or make sure you don't run into one in the future is to make sure you are using DNS servers that conform to standards. The following list includes DNS servers that we have verified conform to standard DNS protocol. Once changed, you should never find a need to change the DNS servers back to what they were previously.
Level 3 DNS Servers
Google DNS Servers
Configuring your Mac to use alternate DNS Servers
1. Select System Preferences under the Apple drop down menu. (Fig 1.)
2. Click the Network icon under the Network and Wireless section. (Fig 2.)
3. Select Ethernet or AirPort (depending on your active connection) from the left hand side of the Network page. (Fig 3. & 4.)
4. For Ethernet: Change or add DNS servers under the DNS Servers: box, seperating each by a comma. Use two from the list above. (Fig 5.)
Fig 5. (Ethernet)
For Airport: First select DNS from the middle menu. (Fig 6.)
Fig 6. (AirPort)
First delete existing DNS servers using the - button near the bottom of the page. Next use the + button and add two DNS servers from the list above. (Fig 7.)
Fig 7. (AirPort)
The DNS servers referenced in this article are different than the name servers you use to point your domain name to MacHighway. This article speaks of the DNS server your computer or network uses. There are several (very thick) books written about DNS and it's functions, however, for this article we will be focusing on using DNS servers that conform to standards so you don't run into issues pulling up your site or accessing your email if a change is made on the host end.
DNS stands for Domain Name System and is the naming system used for any resource connected to the internet. The most important function of DNS for you, as a website owner, is translating the numerical data associated with your domain name into meaningful information computer networks can use to locate your website site, email address, or anything else related to your domain name.
Unfortunately, many ISP's DNS servers do not conform to standards and limit how often they update their information. This may be good for them as it can potentially lead to saving millions of dollars in bandwidth costs, however, it's not so great for you as an end user. Web hosts often need to move servers or sites to different hardware or locations, and in doing so may require a change to the IP address listed with that site or server. If a change like this is needed the Time To Live (TTL), which dictates how often the current IP information is refreshed, on the server will be set to a short period of time so the downtime for end users is minimal.
For example, if a TTL of 4 hours is set on a server, every server on the internet should be notified within a 4 hour period of a site's new IP address. However, if the DNS servers you are using are not following standards and are set to only refresh with new information every 24 hours, then the downtime (and subsequent confusion and frustration) is greatly extended.