Magento 2.1.18 is the final 2.1.x release. After June 2019, Magento 2.1.x will no longer receive security patches, quality fixes, or documentation updates.
To maintain your site's performance, security, and PCI compliance, upgrade to the latest version of Magento.

Quick start. See logs for failed tests

All failed tests are logged in <magento2_root_dir>/dev/tests/functional/var/log.

This path is set in <magento2>/dev/tests/functional/phpunit.xml, element <env name="basedir" value="<path_to_directory>" />.

All Magento errors are logged in <magento2_root_dir>/var/log.

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