Physical Connectivity; Preparing For High Availability; Configuring High Availability Settings - Dell SonicWall SRA 4200 Administrator's Manual

Physical Connectivity

The X3 interface is the default port used for HA control traffic. The HA link should connect the
X3 ports of the SRA HA Pair.
During normal operation, the primary device is in an active state and services all connections,
while the backup device is in an idle state. When the primary device loses connectivity, the
backup transitions to the active state and begins to service outside connections.

Preparing for High Availability

Before configuring the options on the High Availability > Settings page, prepare your devices
for High Availability with the following steps:
Configure both SRA appliances as separate devices with independent IP addresses on your
Step 1
subnet.
Upload the latest SRA firmware to both devices. High Availability will not work unless both
Step 2
devices have the same firmware version installed.
Connect the X3 interfaces of the two appliances together with a CAT 5E or better cable to
Step 3
ensure a gigabit connection.
Note
In a browser, log in to the primary unit and navigate to the Network > Interfaces page. Confirm
Step 4
that the X3 port is active by checking the Status, which should show 1000 Mbps Full Duplex.

Configuring High Availability Settings

To enable High Availability and configure the options in the High Availability Settings section,
perform the following steps:
In a browser, log in to the primary unit and navigate to the High Availability > Settings page.
Step 1
Select the Enable High Availability check box.
Step 2
Enter a number of milliseconds for the Heartbeat Interval. The heartbeat is used to test the
Step 3
connectivity between the primary and backup devices. The heartbeat interval controls how
often the two units communicate. The minimum is 500 milliseconds (a half second), and the
maximum is 300,000 milliseconds (5 minutes).
Enter a value for the Failover Trigger Level. This is the number of heartbeats that must be
Step 4
missed before failover occurs. The minimum is 4, and the maximum is 99.
In the Primary Serial Number field, type in the serial number of the primary device. The
Step 5
maximum length is 12 characters.
In the Backup Serial Number field, type in the serial number of the backup device. The
Step 6
maximum length is 12 characters.
Click Accept.
Step 7
In the browser, open a new tab and point it to the IP address of the backup unit. Log in to the
Step 8
backup.
Dell SonicWALL recommends that you backup and download the settings for both
SRA devices at this stage.
High Availability Configuration | 231