• 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
  • 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 and Active/Active DPI 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
  • 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
• SonicWall Support
  • About This Document

Configuring Active/Standby High Availability Settings

The configuration tasks on DEVICE | High Availability > Settings are performed on the Primary firewall and then are automatically synchronized to the Secondary firewall.

To configure Active/Standby

1. Navigate to DEVICE | High Availability > Settings.
2. In GENERAL SETTINGS section, do the following:
   1. select Active / Standby from the Mode drop-down field.

   2. Select Enable Stateful Synchronization. This option is not selected by default.

      When Stateful High Availability is not enabled, session state is not synchronized between the Primary and Secondary firewalls. If a failover occurs, any session that had been active at the time of failover needs to be renegotiated.

   3. Click OK in the information dialog displayed.

      

   4. To configure the High Availability Pair so that the Primary firewall takes back the Primary role when it restarts after a failure, select Enable Preempt Mode. This option is not selected by default.

      It is recommended that preempt mode be disabled when enabling Stateful High Availability because preempt mode can be over-aggressive about failing over to the Secondary firewall.

   5. Click OK.

   6. Select Enable Virtual MAC to allow the Primary and Secondary firewalls to share a single MAC address. This greatly simplifies the process of updating network ARP tables and caches when a failover occurs. This option is not selected by default.

      If PPPoE Unnumbered is configured, you must select Enable Virtual MAC.

      Only the switch to which the two firewalls are connected needs to be notified. All outside devices continue to route to the single shared MAC address.

   7. To encrypt HA control communication between the active and standby firewalls, select Enable Encryption for Control Communication. This option is not selected by default.

      Firewall performance may be affected if you choose encryption.

      A confirmation message displays:

      

   8. Click OK.
      

3. In the HA DEVICES section, enter the Serial Number of the SECONDARY DEVICE.

   The serial number for the Primary Device is displayed, but the field is dimmed and cannot be edited.

   

4. In the HA INTERFACES section:

   1. Select the interface for the HA Control Interface.

      This option is dimmed and the interface displayed if the firewall detects that the interface is already configured.

   2. Select the interface for the HA Data Interface.
   3. When finished with all High Availability configuration, click Accept. All settings are synchronized to the Secondary firewall, and the Secondary firewall reboots.