Session in magento 2.4.3 not working on local machine

Question

I have a really big problem with my magento installation, everything was working fine til today - now session in frontend and in backend is not working at all - i can't add product to cart or do anything else because form key is always mismatched with the one on the server and i can't log into admin panel because it just reloads the page when i try to log in.

I tried changing my session storage from db to files - no effect, my timezone is set correctly and there is no error in any of the log files, only through debbuging i found that the problem is with form key.

To be honest, i'm out of ideas as i tried to fix that all day long. Did someone had problem like that before? My setup:

Magento 2.4.3 Nginx server, php-fpm 7.4, Mysql v. 10.4.18-MariaDB
I have my installation on dedicated local web address, not localhost

I don't even know what other information i should provide as i cannot pinpoint the source of the problem, so if you need anything else, I will gladly share

Answer 1

This bug arises due to php.ini variable "max_input_vars". Increase it to 10000 through below php function:

ini_set('max_input_vars', 10000); OR Using linux command line

cd /etc/php/7.2/apache2/ vi php.ini (Open for edit and set max_input_vars=10000) :wq(Press esc and write the mentioned command to save and exit) sudo /etc/init.d/apache2 restart(Restart Server)