When I use my browser to visit a web site, it sometimes fails to load a web page or only displays part of the page. Sometimes I see timeout errors, yet at other times the site loads fine. What’s going on and how can I fix this problem?
This issue seems to be getting more and more common.
There are many reasons why a web page may not load successfully in your browser. Sometimes the problem is one of compatibility. A web site’s developers may wrongly choose to use proprietary coding techniques that not every browser knows how to interpret. You can check for this type of issue by using a different browser to visit the web site in question. That’s one of the reasons why I keep both Safari and Firefox web browsers handy. If a page loads in one browser but not the other, I know it’s a compatibility problem.
One of the most likely causes of a web page not loading is a wrongly configured or poorly maintained DNS (Domain Name Server) system by your ISP (Internet Service Provider). Most Internet users have the DNS system assigned to them by their ISP. Sometimes this is done automatically; sometimes an ISP will give you the DNS server’s Internet address to manually enter into your Mac’s network settings. In either case, the problem is usually at the ISP’s end of the connection.
DNS is a system that allows us to use easily remembered names for web sites (as well as other Internet services), instead of the harder-to-remember numeric IP addresses assigned to web sites. For example, it is a lot easier to remember www.core24.co.uk than 126.96.36.199, which is our actual IP address. If the DNS system is having problems translating www.core24.co.uk to the correct IP address, then the web site won’t load. You may see an error message, or only part of the web site may display.
That doesn’t mean there is nothing you can do. You can confirm whether your ISP’s DNS system is working correctly. If it isn’t (or even if it is), if you wish, you can change your DNS settings to use a more robust server than the one your ISP recommends.
Testing Your DNS
OS X offers various ways to test and confirm whether an operational DNS system is available to you. I’m going to show you one of those methods.
- Launch Terminal, located at /Applications/Utilities/.
- Type or copy/paste the following command into the Terminal window.
- Press the return or enter key after you enter the line above.
If your ISP’s DNS system is working, you should see the following two lines returned in the Terminal application:
www.core24.co.uk is an alias for www.core24.akadns.net
www.core24.akadns.net has address 188.8.131.52
What is important is the second line, which verifies that the DNS system was able to translate the web site’s name into an actual numeric Internet address, in this case 184.108.40.206.
Try the host command if you’re having problems accessing a web site. Don’t worry about the number of lines of text that may be returned; it varies from web site to web site. What’s important is that you do not see a line that says:
Host your.website.name not found
If you get a ‘web site not found’ result, and you’re sure you have entered the web site’s name correctly (and that there really is a web site by that name), than you can be reasonably sure that, at least for the moment, your ISP’s DNS system is having problems.
Use a Different DNS
The easiest way to fix an ISP’s malfunctioning DNS is to substitute a different DNS for the one provided. My favorite DNS system is run by a company called OpenDNS, which offers free use of its DNS system. OpenDNS provides complete instructions for making the changes to a Mac’s network setting, but if you’re having DNS issues, you may not be able to access the OpenDNS web site. Here is the quick scoop on how to make the changes yourself.
- Launch System Preferences by clicking on the ‘System Preferences’ icon in the Dock, or choosing the ‘System Preferences’ item from the Apple menu.
- Click the ‘Network’ icon in the System Preferences window.
- Select the connection you are using for Internet access. For almost everyone, this will be Built-In Ethernet.
- Click the ‘Advanced’ button
- Select the ‘DNS’ tab.
- Click the plus (+) button below the DNS Servers field and enter the following DNS address.
- Repeat the above steps and enter a second DNS address, shown below.
- Click the ‘OK’ button.
- Click the ‘Apply’ button.
- Close the Network preferences pane.
Your Mac will now have access to the DNS services provided by OpenDNS, and the wayward web site should now load properly.