Mirror site

A mirror site is a complete and compliant replica of an existing website with a different URL. Mirror sites are most often used to improve accessibility to the original website and to lighten the load on the computer server that hosts it when it generates too much traffic

Just as our image is reflected in the mirror when we look at ourselves, mirror sites are perfect and tangible copies of an original website

They are useful to Internet users on various levels and in various places since they ensure a good user experience and fast page loading.

There is no doubt that this is an ingenious concept with considerable and interesting advantages. But depending on how they are used, mirror sites can easily be counted among the Black Hat SEO techniques.

This is a multi-faceted technique that needs to be analyzed and studied in great detail.

So :

  • What does the term mirror site mean in concrete terms?
  • What are the advantages?
  • What does it take to create a mirror site?
  • What are the different practices of the mirror site technique?
  • What are the issues and consequences of mirror sites in terms of SEO?
  • What can we learn from the use of mirror sites?

In order to properly address the subject, we will take care, in the rest of this article, to answer all these questions.

Without further ado, let’s get started!

Chapter 1: Mirror site – Site miroir : General

Let’s begin our study of mirror sites by stating a few general points.

1.1) What exactly is a mirror site?

In the computer world and on the web, the term mirror is used to designate the exact copy of a set of files.

Thus by analogy, a mirror site designates a site whose architecture and content are the textual and integral reproduction of another website.

Therefore, when we talk about mirror sites, we are talking about two or more websites having specific URLs while being perfectly identical to each other in content and form.

Simply put, a mirror site is a website (M) that offers exactly the same content as a website (P) called main.

In view of this definition, it seems legitimate to think that the concept of mirror sites directly appeals to the concept of duplicate content (duplicate content)

However, despite some of their obscure characteristics, mirror sites are not categorically Black Hat SEO.

So to speak, the mirroring technique is usually used to prevent or correct network saturation.

Thus, when the main site server (P) is unavailable, users can turn to the mirror site server (M) to access data.

To do this, the mirror sites are hosted on separate servers. They are therefore accessible and available through different addresses around the world.

The existence of mirror sites allows to relieve the host of the main website (the main server) by distributing the high traffic generated on servers located in other geographical areas.

However, what about the real benefits and functioning of mirror sites?

1.2. The benefits of a mirror site

There are many advantages that you can get by creating mirror sites and here is a list of the most important ones

1.2.1. Mirror sites make it easier to reach Internet users located on the other side of the world

The primary goal of mirror sites is to facilitate access to a website’s products and services from anywhere in the world by faithfully duplicating its content on separate local servers

Mirror sites thus represent a true load balancing device since they allow websites with high traffic to operate efficiently by sharing their work among several servers.

When a site initially hosted in France is mirrored on another server in Canada for example, Canadians will be able to benefit from a good connection to the site. Despite the distance, they will be able to get a relatively short server response time.

In other words, mirror sites are created to facilitate access to users who are thousands of miles away from the original server. The mirror server is therefore usually located on another continent to provide a fast and reliable connection to nearby Internet users

1.2.2. Mirror sites allow for faster download speeds of large files

When the original site attracts a lot of traffic, mirror sites can act as a kind of “relay” and make the site’s downloadable files available on other servers. This is most often seen on websites that offer software downloads with regular updates

These sites record a large number of downloads that are distributed on exact copies of the original site for a higher download speed.

This is why the big web and computer companies such as Sun Microsystems, Microsoft and many others have mirror sites where their browser software can be downloaded in an optimal way.

1.2.3. Easy access to censored content

The mirror site technique can also be applied to make censored information available in places where access is restricted or prohibited.

Remember, in 2013, when the Chinese authorities decided to to block people’s access to foreign media publications such as such as The Wall Street Journal, Bloomberg and The New York Times, mirror sites were used to restore access to information and circumvent government censorship.

Apart from evading cyber censorship, mirror sites are also set up to circumvent computer blockages.

Indeed, a website can easily end up blocked and inaccessible after a hacking or any other computer attack

In order to bypass this blocking and allow the users of the website to continue their activities, mirror sites are an efficient solution

To make this bypass possible, all you need to do is to replicate a mirror site on a server dedicated to this purpose by associating the use of a website vacuum cleaner (a tool for replicating and downloading all the data of a website in real time) and that’s it.

Thus, once the original website is blocked, an identical, functional and ready-to-use website will take over.

1.3. The various elements necessary for the creation of a mirror site

For the creation and the good functioning of a mirror site, several elements are necessary:

1.3.1. A powerful server

As you may have guessed, the place of servers in the creation of a mirror site is essential.

It is the basic element to create a mirror site and ideally you need a powerful server, capable of supporting a large load

Indeed, for an efficient hosting adapted to mirror sites, it is advisable to opt for a server guaranteeing a considerable data transfer rate (bandwidth) and having a consequent storage capacity to accommodate all the copied data.

1.3.2. Tools for copying websites

You can probably imagine that to duplicate a website, it will take much more than a simple copy and paste.

The creation of mirror sites requires the use of appropriate and specific replication tools.

As we have seen, website replication can easily be done with the help of a website vacuum cleaner

The website vacuum cleaner is a software that, as its name indicates, allows you to vacuum (copy) all or part of a website, and then archive it on a storage device such as a server.

Comment telecharger completement un site internet

The technique of website replication based on the use of a website vacuum cleaner makes it possible to obtain excellent identical copies

However, it should be noted that original sites designed with a content management system (CMS) will only produce non-functional copies

The result will be, so to speak, only replicas of the static content (i.e. just the html rendering of the web pages) of the site.

Besides the website vacuum cleaner, website backup techniques are also a solution of choice.

Indeed, the incremental backup is a powerful replication solution adapted to the copy of important quantities of data.

Still called incremental backup, it is a particular backup technique that is presented as follows (example established over a week)

  • In a first step (Monday), a complete backup or copy of the original site’s pages and files is made.
  • Then, in a second step (Tuesday), a second backup (the incremental backup itself) is made. This one concerns only the data that have been modified or added since the previous backup (web hosting data, email, for example).
  • In a third step and so on (Wednesday, Thursday…), only the data modified since the last backup will be copied.

This backup scheme is practical and very efficient

It optimizes both the duration of the replication process and the server load (CPU) as well as the storage space occupied by the backup data.

1.3.3. A specific domain name for each mirror site

Duplicate domain names, also known as mirror URLs, are different URLs that lead to the same IP address and offer identical information, hosted on a single server to which they are all connected.

Well, that’s not what we’re talking about here

Mirror sites have their own domain names that lead to specific and different servers.

In general on the web, to designate a mirror site, we start by writing the name of the domain with a number greater than or equal to 2 after the “www”

Thus www2.twaino.com would be a mirror site of the web site www.twaino.com.

When the name www2.twaino.com is entered in the address bar of the web browser, the page displayed will be that of the mirror site. However, although the result is from the www2.tawino.com site, in the address bar, the name www2.twaino.com is replaced by www.twaino.com to reassure the user that he is on the official site of the brand

Finally, it should be noted that there is no official and exhaustive nomenclature for mirror sites

Except the fact that they are commonly used, names starting with www2, www3, www4, www…etc, are not the standard. You are therefore free to name your mirror site as you wish.

For example, a site whose name starts with www2 is not necessarily a mirror site and not all mirror sites start with www2, www3 or www4, etc.

1.4. How to maintain your mirror site

In practice, after its creation, the mirror site is frequently updated in order to ensure the conformity of its content with that of the original site

And for good reason, unlike a mirror (object) which reproduces the image and movements of the one who is mirroring, mirror sites are one-way

Indeed, the mirror site is a frozen copy of the main website. It is therefore able to provide only the static content of the original website even if the latter is a dynamic website.

In other words, a mirror site is unable to provide interactive services related to the original site, such as adding comments and/or new content.

It is therefore often necessary to make occasional modifications to the mirror site files in order to give users the perfect illusion of being on the main site.

In order to establish a smooth operation between the mirror site and the main site, the synchronization of the sites and their files is crucial.

Moreover, it is only thanks to the synchronization of the data that the circumvention of censorship and computer attacks by the mirror site technique is possible

When it comes to a dynamic website, reverse proxy options (reverse relay between users and the network of internal servers) are particularly suitable.

1.5. What should not be confused with a mirror site?

The process of mirror sites by its principle, its operation and its uses, resembles many other techniques, which should be distinguished.

1.5.1. Computer Network Delivery (CDN)

Computer Network Delivery or CDN for short is a set of data replicas hosted on different servers located here and there around the world

While in the case of mirroring, it is the original site itself as well as its content that are duplicated identically, here in the CDN, it is only the cache data of the main site that is duplicated.

Like mirror sites, Computer Network Delivery also makes it possible to facilitate access to information from various locations.

One of the particularities of CDN is that it is able to respond to user requests (e.g., to offer streaming video and/or audio content) even when bandwidth is reduced.

1.5.2. Cybersquatting

Cybersquatting is the unauthorized acquisition, registration and use of Internet domain names that are identical or similar to existing trademarks, company names or personal names.

Le Cybersquatting

This rather detestable practice is similar to identity theft

Generally, the objective is either to :

  • Return the domain name to the rightful owner in exchange for a fee;
  • To profile the domain name;
  • Or, sully the reputation and visibility of the real owner, by performing bad actions in his name.

The actions of a mirror site can be wrongly interpreted by Internet users as being the work of cybersquatting because of the similarity of the domain name with that of the main site.

It should be noted that cybersquatting is rightly considered by many to be counterfeiting, or even a criminal act liable to criminal sanction in certain countries.

1.5.3. Typosquatting

Typosquatting is a URL hijacking technique that consists of purchasing numerous domain names similar to those of well-known websites with intentional typos.

It is another form of cybersquatting based on the possibility that cybernauts may unintentionally make a typographical error when typing a website’s URL into their web browser’s address bar (e.g. www.twano.com instead of www.twaino.com).

The goal here is to get as many visitors as possible by taking advantage of the reputation of other websites.

This practice is typical of hackers, who create for malicious purposes, alternative websites that imitate the appearance and usability of the intended destination

Thus, the Internet user does not realize that he is on a different site from the one he intended to visit

We can therefore understand how the technique of mirror sites can be similar to that of typosquatting.

The typosquatter can then proceed to steal personal information (identifiable, passwords, secret codes, and others).

Worse still, they can use this little lack of attention on the part of the Internet user to download malware (malicious files) onto their device (smartphone, tablet, PC or server)

In rare cases, typosquatters simply offer services and products that compete with the original site.

1.5.4. Phishing

The term phishing is used to designate a cybercriminal technique whose murder weapon is nothing more than a disguised e-mail

Le Phishing

Indeed, it is a cyber attack not based on a computer flaw, but rather on the naivety and negligence of Internet users.

The hacker deceives the Internet user by pretending to be a trusted entity (his bank, a member of his company, for example) in order to obtain confidential information.

Licence Logiciel

These hackers go as far as replicating an organization’s entire website (like a mirror site), waiting for the Internet user to connect to it in order to extort his connection data and other personal information.

This is the most widespread and popular cyberattack technique among criminals, who have been working hard to make it more sophisticated over the years.

Chapter 2: The challenges of mirror sites

The use of mirror sites and their SEO issues are numerous and diversified.

Spamdexing is to Black Hat SEO what darkness is to night

It is a set of prohibited techniques, essentially based on the use of fake links that allow the abusive referencing of web pages in the SERPs

If web spam is illegal, it is simply because it allows to deceive the algorithms algorithms of relevance of search engines.

Unfortunately, the illegal use of mirror sites to promote the ranking and accessibility of a site is a heavily used spamdexing technique.

Indeed, the mirroring process is deliberately used to artificially increase the presence and relevance of sites on search engines.

This method appreciated by Black Hat SEOs combines duplicate content with the use of link farming on mirror sites.

The link farming to make it simple is to create a group of several websites that make reciprocal links to each other

Still called link farm, it is a fraudulent technique that allows to improve the ranking of each site in this network in the SERPs.

To do this, the link farm plays on one of the many criteria of PageRank (rating) of websites on search engines: the number of backlinks.

Indeed, the more backlinks there are to a website, the more popular it becomes with the PageRank algorithms and the higher it will be positioned in the search engine ranking.

In our context, the websites of the link farm are nothing but mirror sites. Therefore, they are one and the same site (logical entity) that exchanges reciprocal links (physical entity).

The application of this technique using mirror sites is one of the least ethical forms of link farming.

The discovery of these sites by search engines usually leads to the pure and simple deletion of the entire network of mirror sites from their index.

2.2. Mirror sites and White/Gray Hat SEO

Contrary to what one might think, mirror sites are not only used on the dark side of SEO

Yes, they are not systematically used for dishonest and illegitimate purposes.

2.2.1. The White Hat SEO side of mirror sites

We now know the role of mirror sites in improving the accessibility and functioning of large-scale download platforms and other sites offering high-resolution visuals, videos or heavy animations.

The creation of mirror sites for these types of websites allows them to function well, be accessible and available in several regions of the world.

When the content of these mirror sites is translated into other languages, the results obtained are no longer considered as mirror sites.

These translated copies of the original website are an integral part of White Hat SEO.

And for good reason, such sites are different in the form of their content even if the meaning is the same

Moreover, they are hosted on servers located in different geographical areas and specific to their language of translation.

In addition, the various language versions of the main website are most often accessible from a home page, where their URLs are well listed

The original version of the website is kept without being blocked in the robots.txt file and the value nofollow value of the rel attribute (rel = “nofollow”).

2.2.2. The borderline technique of mirror sites: Gray Hat SEO

In life as in SEO, nothing is ever all white or all black. It is therefore appropriate to highlight the Gray Hat SEO side of mirror sites.

Here the technique of mirror sites is used in a rather particular way with the intention of fooling the indexing robots of search engines in a harmless way

Indeed, search engine crawlers are algorithms that are only capable of capturing and processing textual content (words and/or expressions).

Using this flaw, mirror sites strictly identical in content and not in form are created.

The content of these mirror sites is thus transformed so that the information offered to users on all the sites is the same only in terms of meaning and idea

Thus, the texts are reformulated, the titles, the logo as well as the keywords are modified, by professionals in order to perfect the technique.

Consequently, in their prospecting, the search engine robots will not suspect the deception, and will go as far as to approve the mirror sites and even enhance their backlinks.

2.3. Mirror sites in flash mode

Until recently, websites entirely made of Flash animations, were poorly referenced by search engines.

And for good reason, the indexing robots of search engines had until then, great difficulty to recognize, analyze and understand the programming language used (ActionScript).

It seemed logical then, to facilitate the optimization and referencing of a website based on Flash animations, to set up a mirror site in html or xhtml.

However, such a solution is no longer relevant today, because the majority of search engines and particularly Google can identify, understand and decipher the various animations.

It is therefore necessary to prohibit the access of the mirror site to the indexing robots of search engines

To do this, it is advisable, at the level of the robots.txt file (Disallow), to block the mirror site and to set the non-standard value ( nofollow ) of the rel attribute in the respective lines of code.


2.4. Google’s position on mirror sites

One thing is certain, this is not a straight line.

The search engine invests a lot of effort in the search for mirror sites, which it takes care to penalize in one way or another.

Thus, the mirror sites that are removed from the Google index are those that try to deceive the search engine and its robots through tricks and dishonest tricks.

On the other hand, if a mirror site is brought to the attention of the search engine and it does not disappear from the Google index within a few hours, it does not mean that Google has pardoned it or that it does not plan to eject it from its index.

Google does not indiscriminately remove mirror sites from its database

The search engine, thanks to its powerful algorithms (the Googlebots), apprehends and analyzes each mirror site in detail before deciding on its sentence

The search engine has to act with meticulousness when it comes to mirror sites

And for good reason, for short periods of time, Google uses the mirror site technique to test the operation of its filters with the intention of improving its algorithms.

Chapter 3: Mirror site – Site miroir : For or Against?

Should we use the mirror site technique or not?

3.1. Arguments for the implementation of mirror sites

The uses of mirror sites are numerous and important. The legitimate and justified deployment of mirror sites, as well as their multiple advantages, testify to their benign, favorable and necessary character for SEO.

Thus, the following legitimate uses are associated with the mirroring process

  • To set up an efficient backup system;
  • Carry out comparative tests between the main site and its replicas in order to appreciate, for example, the power of the different servers and their statistical impact on traffic;
  • Preserve the contents of a website (or a page) that is closed or about to be closed
  • Download large files quickly, even for users who are a thousand miles away from the originating server
  • Bypass censorship for freedom of information
  • Balance server loads to ensure a better user experience
  • Counteract a temporary traffic spike on the original site
  • Improve search engine rankings;
  • Bypass firewalls or other computer unblocking programs
  • Etc.

3.2. Arguments against the creation of mirror sites

The arguments against the use of the mirroring technique are, as a general rule, quite numerous and, to say the least, very convincing.

3.2.1. The existence of other more effective alternatives to the creation of mirror sites to increase the traffic of a web site

Although the use of mirror sites has some interesting advantages, it is important to keep in mind that these advantages are not specific to them

Indeed, there are many ways and techniques to obtain the same results without having to create mirror sites.

And for good reason, it is quite possible, for example, to increase the traffic of a website without having to duplicate it in several versions.

3.2.2. The use of mirror sites for fraudulent purposes

The notion of good would lose its meaning if the notion of evil did not exist

When we take into account all that has been said so far, it seems obvious that the mirror site technique can be used for dubious purposes.

Indeed, mirror sites are used among others to :

  • Attempt to improve in a fraudulent way, the PageRanking of websites and their positioning in the SERPs;
  • Illegally make revenue in terms of advertising;
  • Plagiarize a website that is sometimes a competitor;
  • Etc.

3.2.3. The numerous disadvantages of a mirror site

There are certainly advantages, but also disadvantages for the creation of mirror sites.

Indeed, the technique of mirror sites has many limits. We can thus quote :

  • The obvious and catastrophic notion of duplicate content that is associated with it;
  • The obsolete nature of its use for SEO optimization of websites;
  • Its strong affiliation to spamdexing and its numerous uses in Black Hat SEO;
  • Its anti-SEO effects, notably the dilution of the popularity of the main site, when some websites link to the mirror site;
  • The difficulty in distinguishing the original site from its copies;
  • The sometimes distorted identity of the main site;
  • The confusion between the mirror site process and phishing, cybersquatting or typosquatting techniques;
  • The consequences of such confusion on the trust of the users towards the original site;
  • If the mirror site is not continuously updated, users will have to wait for the renewal and the addition of the missing elements;
  • Setting up mirror sites requires the installation of several servers, which means more expensive maintenance costs;
  • And many others.

3.3. Finally, should I use the mirroring technique?

After weighing the pros and cons, it appears that the use of mirror sites offers, on the one hand, a certain number of non-specific and more or less substitutable advantages

On the other hand, the technique collects many disadvantages and it intervenes in the application of many unethical techniques

To top it all off, the search engine Google is busy tracking down and punishing mirror sites and their original sites.

So it is agreed that the arguments against outweigh the rest.

Perhaps it would be better to avoid mirror sites.

Rather than taking unnecessary risks overall, it is better to opt for permanent redirects to a single website (the 301 redirectionredirection, 308 redirection and others)

A technique that gathers all the advantages offered by mirror sites while protecting them from their disadvantages.

Chapter 4: Frequently asked questions

4.1. What is a mirror site?

In general, in computer science, the concept of a mirror refers to an exact and conforming copy of a set of data. On the Net, when we talk about a mirror site, we are talking about an exact copy of an existing web site that has been hosted on a separate server with its own domain name.

In other words, a mirror site is a site M that duplicates the content of a site P, but on a different server.

Of course, if the owner of the site wishes, he can legally duplicate a version of his site accessible on a distinct URL in order to balance the server loads and offer a better experience for his users

However, it must be recognized that mirroring can be used for fraudulent purposes such as setting up a Link Farm network or extorting personal data from users

In these cases, mirroring can result in a Google penalty or lawsuit

4.3. What are the benefits of mirroring?

Mirroring a website has some interesting advantages such as

  • Preserving the contents of a closed or soon-to-be-closed website (or page)
  • Downloading large files quickly, even for users who are a thousand miles away from the original server
  • Bypass censorship for freedom of information
  • Balance server loads to ensure a better user experience
  • Counteract a temporary traffic spike on the original site
  • Improve search engine rankings;
  • Bypass firewalls or other computer unblocking programs
  • Etc.

4.4. What are the disadvantages of a mirror site?

Despite the advantages that you can benefit from creating a mirror site, the practice also has disadvantages that are not negligible such as

  • The duplicate content side which is a fraudulent practice classified as Black Hat SEO
  • The dilution of the popularity of the main site;
  • The difficulty for Internet users to recognize the original version of the site
  • Confusion between mirroring websites and other cyber attack techniques
  • Lack of trust in the ranks of Internet users;
  • Delay of the original website’s information if the copied versions are not regularly updated
  • The need for more servers makes maintenance costs higher
  • Etc

4.5. What is the difference between mirroring and backing up a website?

Although they may be confusing, mirroring and backing up a site do not mean the same thing and are different in many ways

The notable difference is that when a site is mirrored, all the files and static versions of HTML code it contains are copied and uploaded to the mirror site

This cloned version of the original site can then be easily hosted and visited by Internet users, which is not possible with a website backup.

In conclusion

To conclude, we can say that the technique of mirror sites allows to physically duplicate a website and its content.

The replicas created are for obvious reasons (accessibility, availability, and others), stored on separate servers located around the world

It is a technique that offers rather interesting advantages, but also combines several disadvantages.

It is a technique to be used with caution, and it is sometimes preferable to avoid it in favor of more advantageous and current practices.

That’s it, we’re at the end of our study on mirror sites. I hope that the article was useful to you, do not hesitate to share in comments, your opinions and experiences on the subject.

Thanks and see you soon!

Leave a comment