Magento 2.1.x Notice: 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 PCIPayment Card Industry: Refers to debit and credit cards and their associated businesses. compliance, upgrade to the latest version of Magento. The Magento User Guide 2.1.x remains available in PDF for Open Source and Commerce.
In this section of the guide, you will learn how to perform routine index and cache management operations, back up the system, and use tools that help our Support team troubleshoot and resolve issues.