Formerly part of the Devel module package, Devel Node Access (DNA) displays information related to the node access mechanism of your Drupal installation.
The {node_access} table and functionality are part of Drupal core, but they lie dormant until you install one or more node access modules that supply entries into the {node_access} table. Each node access module provides different strategies for controlling what each user can do with your nodes.
DNA has three audiences:
- It helps Drupal admins understand what is happening on their site, visualize how node access modules interact, verify that their customizations give the intended results, and finally answer the famous question: Why does this user have access to that node?
- It helps module and website support diagnose issues with node access on remote sites by instructing their clients to post screenshots and/or cut&paste listings of DNA output.
- It helps node access module developers implement and test proper behavior of their modules.
DNA is a tool for module and site development; it is not intended to run continuously on production sites, and its output is of no interest to website visitors, but if you run any node access module, DNA will help you with your work.