What is the reason for the Bitrix database error SQLSTATE[HY000] [2002] No such file or directory (2002)?

Question

PHP

There is a site. It is deployed on cms bitrkis. intec template. Located on Vps, the site has a CentOs 7 environment. Everything worked, an error suddenly appeared.

The last thing that was done with the site was changing the CNC in the infoblock. After some time, an error appeared.
Technical support checked, they said there is access to the database, everything works, there are no prerequisites for such an error.
I went via ssh, checked if the database is really available and if mysql is working.
In the console it gives such information.
As a result, mysql works and you can connect to the database.
Only one page is available on the site, the authorization page in Bitrix. As soon as you enter your login / password there, the same error occurs.
What could be the reason? After all, the server works well, the problem, it seems to me, is in Bitrix, but what could break it like that, really changing the cnc.

Answer 1

Gentlemen, the issue is resolved! Bitrix was updated the day before. And the intec template itself was not ready for such a development. They have their own update for the new version of bitra, where they fixed incorrect work with the database.
Updated intec core, everything works