Prestashop error 500 due to a Server Migration

[EliasHM]

Hey guys, 

I want to put everything in context so everything is as clear as it can. I was notified that my server was going to be updated due to deprecation, so my host provider migrate my unit from CentOS7 to AlmaLinux 9. Due to this change, I had to update all the websites in my server, including a Prestashop site that I've developed, kanini.mx.

This site is a Prestashop 1.7.8.11 and I was concerned with the deprecation of the PHP 7.4, it would go useless. The host provided said that the AlmaLinux would only provide PHP 8.0 version onwards, but when the migration was completed, still a PHP 7.4 was available, therefore the site still works properly. Now i'm trying to upgrade the site to a 8.1 Prestashop version, in order to work with the most recent PHP versions.

Therefore I created a test environment so I could make all the testing without affecting the actual site (In case something broke). I made the installation from the backup I created before the migration on the following url demo.cuevano.mx/kanini but I get Error 500, and if I activate the debug mode, the site is visible without the html (image 1), but not error message is displayed.

On the error log from the server I get this message 

[Tue Nov 26 18:22:17.465820 2024] [lsapi:error] [pid 3159983:tid 3160107] [client 187.188.23.167:0] [host demo.cuevano.mx] Backend fatal error: PHP Fatal error:  Uncaught PrestaShop\\PrestaShop\\Core\\Data\\Layer\\DataLayerException: Unable to persist data in cache data layer in /home/eliashm/public_html/demo/kanini/src/Core/Localization/CLDR/DataLayer/LocaleCache.php:122\nStack trace:\n#0 /home/eliashm/public_html/demo/kanini/src/Core/Data/Layer/AbstractDataLayer.php(196): PrestaShop\\PrestaShop\\Core\\Localization\\CLDR\\DataLayer\\LocaleCache->doWrite()\n#1 /home/eliashm/public_html/demo/kanini/src/Core/Data/Layer/AbstractDataLayer.php(103): PrestaShop\\PrestaShop\\Core\\Data\\Layer\\AbstractDataLayer->saveReadPropagationResult()\n#2 /home/eliashm/public_html/demo/kanini/src/Core/Localization/CLDR/LocaleDataSource.php(62): PrestaShop\\PrestaShop\\Core\\Data\\Layer\\AbstractDataLayer->read()\n#3 /home/eliashm/public_html/demo/kanini/src/Core/Localization/CLDR/LocaleRepository.php(58): PrestaShop\\PrestaShop\\Core\\Localization\\CLDR\\LocaleDataSource->getLocaleData()\n#4 /home/eliashm/public_html/demo/kanini/src/Core/Localization/Locale/Repository.php(173): PrestaShop\\PrestaShop\\Core\\Localization\\ in /home/eliashm/public_html/demo/kanini/src/Core/Data/Layer/AbstractDataLayer.php on line 198\n, referer: https://demo.cuevano.mx/

On different blogs I've read, they said that it was due to NIGIX and PHP-FPM (which I activated the fisrt one, but the second one only allows me to the 8.2 PHP version or onwards)

The settings are (For both testing and production)
PHP 7.4
Prestashop 1.7.8.11

The production site works fine, but I'm lost, I don't know how to solve the testing environment in order to upgrade to 8.1 to see if everything works properly in order to reproduce the change to the production site.

Thanks 

[EliasHM]

Thanks Cris for the support, I'll check on the things you said.