Error: An error occurred while trying to submit the form (error: Forbidden)

This error occurs when you have high data and while trying to make changes in the User-Server group in Access Control.

To resolve the above error, you can increase the values for max_input_vars, max_execution_time, memory_limit, post_max_size, and upload_max_filesize in the php.ini file by editing. Refer to the below step.

root@gateway:~# nano /etc/php/8.1/apache2/php.ini ---> (change into corresponding PHP version)

max_execution_time = 300
max_input_vars = 10000
memory_limit = 1G
post_max_size = 1G
upload_max_filesize = 1G

And restart the Apache web service.

root@gateway:~# systemctl restart apache2

To Check the php.ini file

root@gateway:~# grep -v '^\s*#' /etc/php/8.1/apache2/php.ini | grep -i 'max_input_vars = \|max_execution_time\|post_max_size\|upload_max_filesize\|memory_limit'

max_execution_time = 300
max_input_vars = 10000
memory_limit = 1G
post_max_size = 1G
upload_max_filesize = 1G