Configuring Advanced Settings - SonicWALL SonicOSX 7 Getting Started Manual

Configuring Advanced Settings

To configure advanced settings:
1. Navigate to DEVICE | High Availability > Advanced.
2. Adjust the Heartbeat Interval to control how often the security appliances in the Active/Standby pair
communicate. The default is 1,000 milliseconds (one second), the minimum value is 1,000
milliseconds, and the maximum is 300,000. A heartbeat interval of at least 1000 is recommended.
3. Set the Failover Trigger Level to the number of heartbeats that can be missed before failing over.
The default is five, the minimum is four, and the maximum is 99.
This timer is linked to the Heartbeat Interval timer. If the Failover Trigger Level is set to five and
the Heartbeat Interval is set to 10000 milliseconds (10 seconds), it takes 50 seconds without a
heartbeat before a failover is triggered.
4. Set the Probe Interval to the interval, in seconds, between probes sent to specified IP addresses to
monitor that the network critical path is still reachable. This interval is used in logical monitoring for
the local HA pair. The default is 20 seconds, and the allowed range is five to 255 seconds.
A probe interval of at least five seconds is recommended.
5. Set the Probe Count to the number of consecutive probes before SonicOSX concludes that the
network critical path is unavailable or the probe target is unreachable. This count is used in logical
monitoring for the local HA pair. The default is three, and the allowed range is three to 10.
6. Set the Election Delay Time to the number of seconds the Primary security appliance waits to
consider an interface up and stable. The default is three seconds, the minimum is three seconds, and
the maximum is 255 seconds.
7. Set the Dynamic Route Hold-Down Time to the number of seconds the newly-active security
appliance keeps the dynamic routes it had previously learned in its route table. The default value is
45 seconds, the minimum is 1 second, and the maximum is 1200 seconds (20 minutes).
In large or complex networks, a larger value might improve network stability during a failover.
8. If you want Failover to occur only when ALL aggregate links are down, select Active/Standby
Failover only when ALL aggregate links are down. This option is not selected by default.
SonicOSX 7 Getting Started Guide for the NSsp Series
Configuring High Availability
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