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CDAP generates log files, following the settings in the configuration file logback.xml, using Logback. Logs (for Distributed CDAP) are located in /var/log/cdap. For CDAP Sandbox, they are located in <CDAP-HOME>/logs.
If you have CDAP Security enabled, then you will have an additional file, cdap-security.xml (documented in an appendix), with additional settings.
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