Configuring Layer 2 Bridge Mode Procedure

Choose a topology that best suits your network. In this example, we will be using a topology that most closely resembles the Simple L2 Bridge Topology.

Choose an interface to act as the Primary Bridge Interface. In this example, we will use X1 (automatically assigned to the Primary WAN).

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NOTE: For information on choosing a topology and interface, refer to L2 Bridge Interface Zone Selection,
Topics:
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Configuring the Primary Bridge Interface
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Configuring the Secondary Bridge Interface
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Engage Physical Bypass on Malfunction
Configuring the Primary Bridge Interface
1
Navigate to the Network > Interfaces page.
2
Click the Configure icon for the X1 (WAN) interface.
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NOTE: Configure the interface with a Static IP address (for example, 10.203.15.82).

The Primary Bridge Interface must have a Static IP assignment.
3
Configure the default gateway. This is required for the security appliance itself to reach the Internet. (This applies only to WAN interfaces.)
4
Configure the DNS server. (This applies only to WAN interfaces.)
5
Configure management (HTTP, HTTPS, Ping, SNMP, SSH, User Logins, HTTP Redirects).
6
Click OK.

Configuring the Secondary Bridge Interface

Choose an interface to act as the Secondary Bridge Interface. Refer to L2 Bridge Interface Zone Selection, for information in making this selection. In this example, we will use X0 (automatically assigned to the LAN):

1
On the Network > Interfaces page, click the Configure icon in the right column of the X0 (LAN) interface.
2
In the IP Assignment drop-down list, select Layer 2 Bridged Mode.
3
In the Bridged to drop-down list, select the X1 interface.
4
Configure management (HTTP, HTTPS, Ping, SNMP, SSH, User Logins, HTTP Redirects).
5
You may optionally enable the Block all non-IPv4 traffic setting to prevent the L2 bridge from passing non-IPv4 traffic.
6
Optional: VLAN Filtering ( SonicWall NSA series appliances)

You may also optionally navigate to the VLAN Filtering tab to control VLAN traffic through the L2 bridge. By default, all VLANs are allowed:

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Select Block listed VLANs (blacklist) from the drop-down list and add the VLANs you wish to block from the left pane to the right pane. All VLANs added to the right pane will be blocked, and all VLANs remaining in the left pane will be allowed.
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Select Allow listed VLANs (whitelist) from the drop-down list and add the VLANs you wish to explicitly allow from the left pane to the right pane. All VLANs added to the right pane will be allowed, and all VLANs remaining in the left pane will be blocked.
7
Click OK.

The Network > Interfaces page displays the updated configuration:

You may now apply security services to the appropriate zones, as desired. In this example, they should be applied to the LAN, WAN, or both zones.

Engage Physical Bypass on Malfunction

The “Engage Physical Bypass on Malfunction” option allows you to perform a physical bypass of the firewall when two interfaces are bridged together with LAN bypass capability. This means that the packets between the bridged pairs will continue flowing if an unrecoverable firewall error occurs, that is, if the firmware or NSA series appliance fails. If this option is not enabled, the ports will behave like normal Ethernet ports.

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NOTE: This option is only available when the X0 and X1 interfaces are bridged together on an NSA 7500 or above appliance and on appliances that support the LAN Bypass Module.
To enable this option:
1
Click on the Edit icon in the Configure column for the Layer 2 Bridge Mode Interface you want to configure. The Edit Interface dialog displays.

2
Click the Engage Physical Bypass on Malfunction check box.
3
Click the OK button.