Mirror URLs are a common practice when naming a domain. Still, this seemingly harmless name can be a serious threat to your website’s SEO On Page .
Below you can discover its origin and its main characteristics. Plus, you’ll get some good information about saying goodbye to one of the most common SEO mistakes forever.
What exactly are mirror URLs?
These types of URLs are also known as mirror domains or duplicate domains. It happens when duplicate content exists between two or more different domains . They are traceable on your website both with the slash («/») at the end and without it and usually lead to the same content.
At the end of the day, they are different domains that lead to an identical IP address hosted on a server, since both are connected to it. The following is a clear example of mirror URLs:
- example page.com/blog-seo-branding/
Although it may seem strange, it is something that is seen very often on the network. It is not a fraudulent technique, nor does it pose any type of problem for the user. What’s more, it allows the navigator to access the site regardless of the domain that they type in their browser.
Main causes of its presence
The appearance of the concept of mirror URLs in technological slang can be explained by the behavior of many companies and professionals in the sector. They acquire more than one extension of their domain in order to protect their brand.
With this tactic they achieve another important objective: to prevent third parties from making fraudulent use of their corporate identity.
Currently it is usual to observe companies with various extensions of gTLD domains : .com, .net, .org, etc. It is also quite common to see companies that use international ccTLD domain extensions : .it, .uk, .es, etc.
The craving for omnipresence has led to a whirlwind of acquisitions that has also infected small web page administrators.
The configuration of multiple domains pointing to the same server is due to the current obsession with getting the most traffic possible . To achieve this objective, the administrators of the web pages provide the user with access to their sites regardless of the domain extension entered.
These decisions often have counterproductive results for companies. The most notorious is that navigation between mirror domains leads to the same content. Likewise, the consequences for the SEO positioning of these websites can be very negative in the long term.
How to know if your site has mirror URLs
As with other duplication cases, replicated URLs can reduce performance . Therefore, it is essential to identify and resolve any setbacks. For this task, it is best to use the mechanisms offered by the same “judge” who dictates the positioning rules in the SERP.
Google’s Webmaster Tools give you the ability to see which pages on your site are duplicated . You can also check all the variations that a URL may have suffered.
Despite being an instrument of tremendous potential, its usefulness is limited for SEO professionals. Thanks to it, the duplication of parameters problems will be eliminated, but its results will only affect Google and Bing. For portals such as Twitter or Facebook it is not possible to use the possibilities provided by the Google Search Console.
Consequences of having duplicate URLs on the web
These mirror URLs are different links in the eyes of Google, that is, there is more than one way to access the same content. This is due to two main causes: the web links are not properly optimized or those that link to your page externally through backlinks are not properly configured.
The tracking robots of the almighty search engine classify mirror domains as duplicate content and this is highly dangerous for the positioning of the web, regardless of the domain in which it is indexed. With the update of Google’s Panda ranking algorithm, any hint of duplication can be dramatic for any website.
In these duplication situations, it is usual that only one of the domains hosted on the same IP is positioned correctly. Due to this, the rest are practically relegated to irrelevance for Google. It may even happen that the oldest domain, or the first one found by the search engine, is the one that obtains the greatest significance.
The PageRank may also be affected by a malpractice with mirror URLs. These links divide the relevance of a domain and reduce the importance that a powerful URL can have . If it happens on a large scale, it could lead to a Crawl budget problem , which would cause Google to crawl more links than it should to access the same content.
How to definitely kill your mirror URLs
The way to end once and for all the headaches that can cause duplicate content between your different domains is as follows:
- Use the appropriate tools to analyze all the URLs on your website . Thanks to platforms like Screaming Frog or SEMrush , for example, you can see the problematic links and correct them. Also, if these duplicate domains receive external links from other pages than yours, it is best to perform a 301 redirect from the mirror URL to the appropriate URL.
- Apply the label “no index” . It must be used in each and every one of the domains that you consider irrelevant for its null contribution to the web. In this way, Google only indexes the main page, ignoring the others.
- Use the “canonical” tag . It is a more laborious option, but much more effective than the previous one. It consists of placing this label on each of the pages that are duplicating content in the direction of the corresponding tab. With this technique, in addition, the rest of unaffected pages remain visible. For example: <link rel = ”canonical” href = ”http://www.dominioprincipal.es/discos-segunda-mano/elkar/bilbao.html“ />
- Correct labels for desktop and mobile versions . For the desktop version, insert the link link rel = ”alternate” tag ; In this way, the Google tracking robot is warned that there is an alternative to the desktop version. Similarly, the link rel = canonical tag must be applied to each and every page of the mobile version, pointing to the corresponding pages of the desktop version.
Little tricks that can make a difference
If the above indications do not give you the expected result, you can try the following tips :
- Use Google Search Console . This valuable tool will serve you to modify the parameters that do not generate unique content. It is recommended to establish a routine so that all the links to be entered in the future follow the same format.
- Set up robots.txt well . Do not allow URLs to be incorrect, this will improve the effectiveness of search crawlers.
- Asks to change the URL located on another page . It is common to find poorly written links on pages that link to ours. In this case, the easiest and fastest way is to send an email to the webmaster requesting that the correct URLs be entered correctly.
Clear and simple URL writing avoids problems
There are some recommended follow-up guidelines to avoid the problems that mirror URLs can cause. In this way you guarantee that the people who visit your website see the content you want.
- Consistent writing is paramount . The format that is given to the links must be simple and meaningful. Likewise, avoid linking to http: //www.paginaejemplo.com/pagina/ , http://www.paginaejemplo.com/pagina and http://www.paginaejemplo.com/pagina/index.htm .
- Try to use 301 redirect . If you have structured your URLs, in order to correctly indicate both visitors and crawling spiders . You can do it through the .htaccess file and in IIS with the administration console.
- Use top level domains . If your website offers content for an audience in a specific country, the URL must be properly configured. For example, if the page is directed to Italy, it should be http://www.paginaejemplo.it , not http://www.paginaejemplo.com/de
- Make it easier for Google robots . It is not convenient to block the technological giant due to possible future negative repercussions. Allow your crawlers access to your duplicate URLs, even if you use the robots.txt file. By not having permission to crawl pages that host duplicate content, they don’t discover that URLs point to the same content. In this way, they are considered unique pages and without any link.
- Take care of the contents of your site . Try to have the least number of pages that talk about the same topic. Group similar content under the same link, or expand the content so that a separation is necessary. All this implies the writing of URLs of different formats, in addition to avoiding creating identical URLs. For example, http://www.ejemplo.com/conoce-paris and http://www.ejemplo.com / knows-paris-in-two-days.