Some of our firewalls support the implementation of Device-HA Pro solution in which a backup firewall (same device model) automatically takes over the function of the active firewall if it should fail.
Do I need all licenses (UTM licenses as an example) twice when using Device HA Pro?
No, if two firewalls are used with Device HA Pro, only one license is required. The passive firewall takes over the licensing of the master when the active firewall should fail.
Both devices must be the same model and registered in the same myZyxel.com account.
The licenses have to be transferred to the active device. When the active firewall fails, every license will be automatically transferred to the passive firewall.