Difference between Primary and secondary device.

This article will explain about the difference between a Primary and Secondary device.

Primary Device: Describes the principal hardware unit itself. The Primary identifier is a manual designation and is not subject to conditional changes. Under normal operating conditions, the Primary hardware unit operates in an Active role.
NOTE: All the services are activated on this device.

Secondary or HA device:  High Availability (HA) allows two identical SonicWall security appliances running SonicOS to be configured to provide a reliable, continuous connection to the public Internet. One SonicWall device is configured as the Primary unit, and an identical SonicWall device is configured as the Secondary unit. If the Primary Dell SonicWall fails, the Secondary SonicWall takes over to secure a reliable connection between the protected network and the Internet. Two appliances configured in this way are also known as a High Availability Pair (HA Pair).

High Availability provides a way to share SonicWall licenses between two SonicWall security appliances when one is acting as a high-availability system for the other. Both appliances must be the same SonicWall model.

To use this feature, you must register the SonicWall appliances on MySonicWall as Associated Products.

NOTE: No services or keys can be activated on a Secondary/HA device.

Once both the devices are registered you can associate them - How do I associate an HA pair in MySonicWall.com?

To disassociate the HA from the Primary follow the article - How do I disassociate an HA pair in MySonicWall.com?

TIP: To activate services or keys on an HA/Secondary device it needs to be converted to a standalone unit, for which a HA conversion to standlone key needs to be purchased- How do I purchase the HA-to-Standalone Conversion Key?