PAN-OS is the software that runs all Palo Alto Networks next-generation firewalls. Palo Alto Networks also frequently publishes updates to equip the firewall with the latest security features. The firewall can enforce policy based on the applications and threat signatures (and more) that content updates provide, without requiring you to update the firewall configuration.

After you successfully download and install a PAN-OS software update on your physical firewall, the software update is validated after the physical firewall reboots as part of the software installation process to ensure the PAN-OS software integrity. This ensures that the new running software update is known good and that the firewall is not compromised due to remote or physical exploitation.