By default, Matomo will download and use the Geo IP DB only once for all your blogs instead of doing this for each blog. This works fine in almost every case unless you customise various parts in your Matomo such as the upload path and the directory structure etc. In this case, you can force Matomo to use a specific upload path by defining the following constant in your wp-config.php:

define('MATOMO_GLOBAL_UPLOAD_DIR', '/path/to/network/upload/directory');

This would be needed only if you are using WP MultiSite, e.g. if you are overwriting the upload path through some custom plugin.

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