Will such a site appear in the search results or go to the ban as a duplicate of the main one?

Question

Search Engine Optimization

Hello everyone, I'm asking for advice from SEOs. I don't understand this myself.
There is a main site - in the top of Yandex and Google. The client needs to make an additional sites (30-35 pieces) for Russian cities.

Question: If you make 35 domains for all cities, duplicate the main site there, change the text + pictures, but the page structure (layout) will be the same everywhere, will Yandex and Google let these sites into the search engine or gobble them up as a duplicate at the entrance? If devoured, what is the best way out of this situation? Sub folders or sub domains? How not to step on a rake and not get banned for duplicate content?

Answer 1

In order for search engines not to impose sanctions on the created sites on subdomains, it is necessary to follow a number of rules and the sequence of performing both technical and SEO tasks. Below I will give general recommendations and mention some points, but this is from memory. Somewhere there was a complete instruction on creating and optimizing subdomains, I will provide it upon request, if interested.
General nuances:

• decide on the number of subdomains (for example, million-plus cities);
  
• content substitution conditions (meta tags, headings, ALT, text) so as not to produce duplicates;
  
• naming subdomains based on the analysis of competitors in the search results, for example, in order not to use the full name of cities in the name of subdomains unnecessarily.
  

Further:

1. We create subdomains and make them aliases of the main domain. At this stage, the information on all domains is no different, the sites are complete copies.
   
2. Fuse each subdomain with its www version using 301 redirects. It is highly recommended to use non-www version for subdomains to avoid SSL certificate issue
   
3. To avoid gluing subdomains, as soon as possible after completing the previous paragraph, you need to close them from indexing by writing in robots.txt: User-agent: * Disallow: /
   
4. On all subdomains in the title, meta-description, meta-keywords, H1, you need to replace the mention of the city with a variable, which, depending on the subdomain, will be replaced with the name of the city. We do the substitution on all pages and sections / subsections (do not touch meta tags and H1 of product cards). If necessary, you need to create several variables with cities in different cases. On pages where the toponym is not used in the title and meta-description, it is recommended to create an appendix indicating the current city, depending on the subdomain.
   

Don't miss the technical details:

• Purchase a Wildcard SSL certificate for the domain and subdomains.
  

Yandex Help

1. "Regionality": https://yandex.ru/support/webmaster/site-geography...
   
2. "Designing subdomains": https://yandex.ru/support/webmaster/site-geography...
   
3. "Indexing subdomains": https://yandex.ru/support/webmaster/yandex-indexin...