• High Availability
  • About High Availability
    • High Availability Terminology
    • High Availability Modes
    • High Availability Encryption
    • Crash Detection
    • Virtual MAC Address
    • Dynamic WAN Interfaces with PPPoE HA
    • Stateful Synchronization with DHCP
    • Stateful Synchronization with DNS Proxy
    • About HA Monitoring
  • Understanding High Availability
  • Understanding SonicWall High Availability Operation Modes
  • About Active/Standby HA
    • Benefits of Active/Standby HA
    • Working of Active/Standby HA
  • About Stateful Synchronization
    • Benefits of Stateful Synchronization
    • How Does Stateful Synchronization Work?
    • Example of Stateful Synchronization
  • Active/Standby Prerequisites
    • Supported Platforms and Licensing for HA
    • Physically Connecting Your Security Appliances
    • Connecting the Active/Active DPI Interfaces for Active/Active DPI
  • Maintenance
    • Removing an HA Association
    • Replacing a SonicWall Security Appliance
      • Replacing an HA Primary Unit
      • Replacing an HA Secondary Unit
• High Availability Status
  • Active/Standby High Availability Status
    • High Availability Status
    • High Availability Config
    • High Availability Licenses
• Configuring High Availability
  • Configuration of HA Active/Standby
  • Configuring Active/Standby High Availability Settings
  • Configuring HA with Dynamic WAN Interfaces
  • Configuring Network DHCP and Interface Settings
    • Disabling the SonicOS DHCP Server
    • Configuring Virtual IP Addresses
    • Configuring Redundant Ports
• Fine Tuning High Availability
  • Advanced Settings
  • Configuring Advanced High Availability Settings
• Monitoring High Availability
  • Configuring Active/Standby High Availability Monitoring
  • IPv6 High Availability Monitoring
  • IPv6 HA Monitoring Considerations
• Failure Monitoring
• SonicWall Support
  • About This Document

Understanding High Availability

High Availability is designed to alleviate or eliminate

• System downtime
• Single points of failure
• Increased system load

A good high availability solution considers scale as well as workload.

SonicWall HA allows two identical firewalls running the Management Service to be configured to provide a reliable, continuous connection to the public Internet. One firewall is configured as the Primary unit, and an identical firewall is configured as the Secondary unit. In the event of the failure of the Primary firewall, the Secondary firewall takes over to secure a reliable connection between the protected network and the Internet. Two firewalls configured in this way are also known as a High Availability Pair (HA Pair).

HA provides a way to share licenses between two firewalls when one is acting as a high availability system for the other. To use this feature, you must register the firewalls on MySonicWall.com as Associated Products. Both firewalls must be the same SonicWall model.