Saved charts can be viewed in the Dynatrace Portal indefinitely, as long as the timeframe charted is dynamic and there is no set expiration date. However, the emailed link for a saved chart is valid only for a few hours after the email was sent. This is because the image files for reports and for saved charts reside in a temporary directory on the Portal web server. These directories are regularly purged to ensure that the directories do not grow large enough to affect the health of the servers.
People who receive an emailed link for a saved chart need to have access to the Dynatrace Portal to view the chart. If the test is expired or inactivated, the public URL will link to an empty chart. If the test is deleted, the public URL will go to an error page.