On the test, I will update the phpBB 3.1.9 forum to the version of phpBB 3.2.2.
System requirements phpBB 3.2 if necessary, you can see here https://www.phpbb.com/support/docs/en/3.2/ug/
Be sure to make a backup copy of the database and forum files.
I recommend that you perform an update on the test virtual server, running a copy of the forum from the backups, because in my case there were errors and it took them a while to fix them, and then you can update them to the main one in a similar way quickly.
We proceed to update, download the archive with the new version of phpBB 3.2.x and unpack it:
wget https://www.phpbb.com/files/release/phpBB-3.2.2.zip unzip phpBB-3.2.2.zip
In the unpacked forum data, delete the file config.php and these directories: files/, images/, store/.
In the phpBB data, what’s on the web server will be deleted except for the ext/, files/, images/, store/ and config.php file.
Move the remaining downloaded data to the directory with the forum data, agree to overwrite the file in the ext/ directory.
If the rights to files and owner change, for example, you can specify them as follows:
sudo chown -R www-data:www-data /var/www/forum/
If the database of the forum is large, then you can execute the command in the root directory of the forum:
php ./bin/phpbbcli.php db:migrate --safe-mode
Open the forum address in the browser by adding /install/app.php/update or /install/database_update.php at the end, select the “Update” tab, select “Update database only”, start the update process and wait for the completion.
After the successful update, delete the install directory:
See also my articles:
Solution of error “A module already exists” and “The installer detected a timeout” when updating phpBB
Import and export MySQL databases
Updating phpBB 3.1.8 to phpBB 3.1.9
Updating phpBB 3.0.x to phpBB 3.1.x
Other about phpBB