When you are ready to activate changes that you made to the candidate configuration on Panorama or to push changes to the firewalls and Log Collectors that Panorama manages, you can Preview, Validate, or Commit Configuration Changes. For example, if you add a Log Collector to the Panorama configuration, firewalls cannot send logs to that Log Collector until you commit the change to Panorama and then commit to the Collector Group that contains the Log Collector. Panorama queues commit operations so that you can initiate a new commit while a previous commit is in progress. If the queue already has the maximum of ten administrator-initiated commits, Panorama must process a pending commit before you can initiate a new commit. You can also Use the Panorama Task Manager to cancel pending commits or to see details about commits that are pending, in progress, completed, or failed. To check which changes a commit will activate, you can run a commit preview.
For details on candidate and running configurations, see Manage Panorama and Firewall Configuration Backups. To prevent multiple administrators from making configuration changes during concurrent sessions, see Manage Locks for Restricting Configuration Changes.
When you initiate a commit, Panorama checks the validity of the changes before activating them. The validation output displays conditions that block the commit (errors) or that are important to know even though they don’t block the commit (warnings). For example, validation could indicate an invalid route destination that you need to fix for the commit to succeed. To identify and fix configuration errors before initiating a commit, you can validate changes without committing. A pre-commit validation displays the same errors and warnings as a commit, including reference errors, rule shadowing, and application dependency warnings. Pre-commit validations are useful if your organization allows commits only within certain time windows; you can find and fix errors before commit time to avoid failures that could cause you to miss a window.

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