Increase the max_input_vars in WordPress can be done in several ways. Here is how to increase the max_input_vars value in different ways and then how to confirm the new value. This post is for Ubuntu 16.04 LTS with PHP7
Set the value in php.ini
In a VPN server you would set the value max_input_var in the php.ini file used by WordPress
sudo nano /etc/php/7.0/apache2/php.ini
Ctrl+W to find in Nano editor:
Save and exit the file in Nano.
Then restart Apache
sudo service apache2 restart
Local php.ini file
Create a file inside the /wp-admin/ folder called php.ini
Add in this line:
max_input_vars = 3000
Increase max_input_vars using .htaccess
Use a text editor to add the following line to the .htaccess file.
Replace 3000 with the maximum number of input variables that you want to allow:
php_value max_input_vars 3000
Save the changes to the .htaccess file and exit the text editor.
How to verify the updated max_input_vars value
Create a file called phpinfo.php
Add this line of code into the phpinfo.php file
<?php phpinfo(); ?>
Navigate to the file on your server for example www.example.com/phpinfo.php
Scroll down to till you find max_input_vars to verify that the value is correct. Or use the search function in the browser and search for:
You should delete or rename the file phpinfo.php when the value of max_input_vars is verified to be correct. You don’t want to give the bad guys a tool to explore your server.
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