DNS speed testing is one of the tools needed to achieve a good performance result for a website. In most cases, those who approach this need – that is, to speed up the loading of pages of a portal – just use the basic tools to monitor the loading speed of the website (which is always a factor in SEO ranking).
I’m talking about names like Pagespeed Insight or Gtmetrix, which are fundamental tools for evaluating the results obtained with optimization activity aimed at the website’s cache, image compression and fonts. But is this enough to get good results? Here’s how to use DNS testing to improve server response and give your publishing project or ecommerce a boost.
What is a DNS speed test and what is it for?
Let’s start with the basics: DNS is a server configuration useful for translating the domain name (the classic www.esempio.it) into the IP address of your website. In a nutshell, without DNS every user would have to remember a long string of numbers to reach your web pages.
Domain Name Systems thus have a practical function. But they can be a parameter to monitor for server speed. That’s why you need to use DNS speed tests!
This tool allows you to keep track of the time it takes to resolve the translation of a domain name to a classic IP. With this check you can find out if there are any problems and bottlenecks that somehow make it difficult to load due to slow resolution.
Must-read: page speed is an SEO factor
Why evaluate DNS resolution?
DNS lookup is the first element that occurs during the loading of any web page. The image below shows well the evolution of this process and the task of DNS.
The computer asks the DNS provider for the IP address of the site in question. This junction, in addition to allowing you to have a human friendly address, is one of the many ingredients that determines the upload time of a Web site. Thus long times for DNS resolution and translation result in a deterioration of Core Web Vitals and especially the parameter known as TTFB.
That is, the time to first byte, which indicates how long a user’s browser browsing online must wait when it is to receive the first packet of data from the server. All this can also negatively affect user experience and search engine optimization.
Remember that DNS resolution allows nodes in a network, i.e., hosts, to be named. Reverse DNS lookup (rDNS), on the other hand, goes the reverse route: it goes back to the host name by knowing the IP.
How to do a useful DNS speed test
There are several tools that allow you to do a good speed check for DNS. One of the best known ways is to use the Domain Information Groper (DIG) command in your computer terminal. This way you can find out what the time is from your machine.
- Windows: go to Start and then to Run. Type cmd and press Enter.
- Apple: click in the applications section and start terminal.
At this point you must type the command time dig iltuosito.com to get the requested information. The Domain Information Groper is used to query DNS servers and reports the time it takes your Web site to get the information it needs. Here is an example.
Specifically, you can look at the query time in milliseconds (the value taken by the computer to execute the command) and the actual time. That is, how long it takes the machine to reach DNS. Now, subtract these values and you have the result: how long it takes DNS to respond.
Other tools for evaluating DNS speed
There are other applications for determining DNS load speed, also in tools for evaluating website performance you can find it. Here, for example, are Pingdom’s results.
As you can see from the image, the tool allows you to check DNS latency. That is, the time it takes for this step to resolve. You can use this tool to estimate values accurately: each time you analyze a new website, the DNS record needed to get the IP is determined.
So you can have realistic information, however in subsequent tests the tool keeps this value cached so the results may be overly favorable. Don’t forget that Gtmetrix also allows you to monitor DNS times in waterfall, all advanced tools for measuring web page load time offer this data. But how to optimize it?
DNS: improve the timing of your website.
Good hosting is the starting point for noteworthy results. However, to improve DNS times we need to give some extra attention to the possibility of eliminating unnecessary requests.
Running your website on Pingdom allows you to work on this very point: identify what is not needed and eliminate it to streamline the number of requests. Or to lighten the load of what is holding back value. In these cases, for example, a good CDN can be particularly useful.
One of the most interesting tricks to speed up the website after a DNS speed test reveals certain flaws: DNS Prefetch. This step allows domain names to be resolved before resources are requested so as to gain a good amount of time.
The result can be achieved by simply analyzing the website with Pingdom, identifying the elements that give the most trouble in terms of DNS and using prefetching in this way.
