Magento 2: 403 error after issuing setup:upgrade command
Step 1 : open the terminal and navigate to magento web root
cd /var/www/html/magento2
Step 2 : Deploy command
php bin/magento s:s:d
Step 3 : Reindex command
php bin/magento i:rei
Step 4 : Set owner command
chown -R www-data:www-data /var/www/html/magento2
Step 5 : Give permission command
chmod -R 777 /var/www/html/magento2
Step 6 : Remove cache command
rm -rf var/cache