To understand what Yandex mirrors are, you need to know the basics of promotion and search engine optimization. In general, a “mirror” is a broad concept that can be interpreted in different ways. Just like there can be several reasons to create or remove it.
Definition
So, most often a mirror means an 80 percent copy of information on one server relative to information on another. If we talk about the site, then we can say that this is a duplicate. Most often, this method is used in order to provide the user with several sources with the same information. Large and significant documents can be located on several mirrors, thereby unloading the servers and speeding up the download.
First option
Yandex or Google mirrors generally have the same interpretation. But there are some differences in the understanding of these definitions. For example, it was originally believed that the mirror of the site represents the existence of two versions with and without www. That is, if you created a site, then you will have two copies: site.com and www.site.com. And all would be fine, but the search engine believes that these are two different sites. Connoisseurs of search engine optimization will say that such a duplicate harms the promotion of your resource.
So that there would be no further problems, and the site did not receive filters and did not go to the ban, webmasters glued copies. All that is required of you is to decide on the domain that is preferred for your site. A copy will be “attached” to it.
Second option
The following interpretation is based on the existence of an identical domain. That is, the domain becomes the mirror, which is attached to the main resource. This usually happens when a new address is glued to the primary. This happens when the webmaster starts another domain and forms a mirror from it. In this case, the main resource becomes the main one, and its mirror will redirect visitors to it. Interestingly, there can be a ton of such copies.
Third option
A Yandex or Google mirror can be a resource, which is an exact copy of another resource. But the difference is that they both have their own individual domains and are located on different servers. Typically, such a trick is used by large companies and online stores that do not want to lose traffic. They create several such copies, but on different servers. If one of the servers failed, all traffic goes to working, to a copy of the resource.
Causes
In this case, you will have a question: why then do Yandex mirrors? Here, as in the case of their typology, there may be different versions. Perhaps you need to bind a new domain, or you need to book one of them. Often mirrors are used in advancement or for safety. Finally, this is an option to rid the filter of the resource. Consider each reason.
New domain
Not everyone immediately becomes experienced users who know the intricacies and pitfalls. Often a beginner decides to whip up a blog or a commercial site. Someone wants to test the work, someone needs it for fun. Therefore, any domain is selected, and a resource is put on it.
After the site begins to generate income, the user decides to take it seriously. But the domain has remained ugly. To fix this, a new name is bought and glued to the first. They make him the main one. Sometimes a change of domain can be caused by the degeneration of a site that changes the subject or becomes expanded. Obviously, the address is no longer relevant.
Reservation
This is another reason why you might need a Yandex mirror. If you understand that your domain may have similar names, for example, Auto-Kiev or Kiev-Auto, then it is better to book all the similar ones. So you protect yourself from competitors and help users find the right resource. Often visitors, knowing the address, make mistakes in it. So that they do not fall on your competitors, you can also book all similar names.
Development
Mirrors may be needed if you decide to monopolize the market. For example, you sell in several regions or even countries. Then you create a site for Russia mysite.ru, Ukraine - mysite.ua, and Belarus - mysite.by. To promote your business, this option is perfect. It is also used if your activity is diverse.
Security and Filters
This option is ideal if you need to secure your resource. Typically, large companies do this. They have competitors or simply ill-wishers who can harm the stable operation of the site. Therefore, in order not to lose traffic at the time of cyber attacks, it can be redirected to a mirror. In this case, the resource is hosted on several servers and can quickly resume work.
If your site falls under the filters (this can happen not only through your fault), then you will want to quickly restore it. In some cases, it is mirrors that save from such prohibitions.
Action robots
Yandex and Google take mirrors a little differently. They have their own behavioral factors that can influence their decision. But in general, if there are sites with the same addresses and content, then the system will definitely perceive this as a mirror. The same situation will occur if a server redirect is installed.
The question arises: “How are resources indexed?” The robot finds them, begins to glue. In this case, only the main mirror will be indexed. Yandex in this case will choose, according to its reasoning, the main resource. If there is an indication of the main mirror, respectively, the robot will follow it.
Customization
If you need to designate one of the resources as the main one, then you can contact a special service. Mirrors are not set up in Yandex.Webmaster, but here you can check which of the resources is considered the main one. If the robot considers it nonprincipal, then it will be added along with the main one automatically. If the two resources are in no way dependent on each other, then they will be displayed separately.
You can assign one of the resources as the main one using the Host directive or install a server redirect. It is important to understand that the whole process takes some time. When the system approves all the changes, then the resource will appear in the search under a new name.
Examples
By the way, it is known that the Yandex.Mail mirror works on a similar principle. The only thing called a little differently. "Alias" is a conditionally new address for sending mail. Regardless of whether you register mail as @ yandex.ru or @ yandex.by, letters will come to you from any address. So, there is @ ya.ru, and @ yandex.com, and @ yandex.ua, and others.
The same story with Yandex.Market. The mirror in this case is not on different servers. “Alias” refers to one resource, but with different names. This option refers to the promotion of resources and is targeted at several countries and regions. Since Yandex is popular not only in Russia but also in other neighboring countries, services such as Post and Market have their own conditional mirrors.