Transferring a wordpress site. Why does it redirect to /wp-admin/install.php?

Question

WordPress

Hello.
I had to reinstall the system on the vps server. Debian 9, Vesta-cp
After the site is migrated, WordPress redirects to /wp-admin/install.php
Server, operating system, nginx+php-fpm. Everything is as it was before the reinstallation.
Transferred as follows
1. transferred all files to the site folder.
2. created a database and then transferred the database files (to /var/lib/mysql)

I don’t understand what the problem is, I need help from more experienced

Answer 1

It looks like it sees the database, but it is empty
1) check the specified table prefix in the config, and that it matches the one in the database
2) Check that you specified the correct database, exactly the one that you poured
Purely theoretically, there are more options and it can not be

Answer 2

wordpress does not see the database, have you changed the settings in wp-config.php?

Answer 3

There is nothing better than the Duplicator plugin) If the solution does not help, do it with it)