Best practices for designing a fault-tolerant web application

Question

MySQL

Good afternoon!
For the purpose of self-development, I want to gain theoretical knowledge and practical experience in the field of building a web service.
Tell me where to look for best practices, what architectures do you use, which ones do you consider the most beneficial in terms of fault tolerance, scalability, endurance under heavy loads and ease of configuration?
Interested in such moments as correct load balancing, fault tolerance, caching servers, databases (again, fault tolerance), backends.
Thanks in advance
ps why nosql db is needed and what role they could play in the requested schemas

Answer 1

Superficially, but as an option www.insight-it.ru/highload