Configuring Advanced Site to Site Settings
Quantum Spark 1500, 1600 and 1800 Appliance Series R80.20.40 Locally Managed Administration Guide | 242
Configuring the Appliance Interfaces
Link Selection is used to:
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Specify which interface is used for incoming and outgoing VPN traffic.
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Determine the best possible path for the traffic.
In addition, with the Link Selection mechanisms, the administrator can select which source IP addresses are
used for VPN traffic.
The default configuration to select an outgoing interface and source IP address is for the device to
determine them automatically. Alternatively, you can change the default settings and select other means to
determine:
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The appliance's outgoing interface
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The appliance's source IP address
To configure the appliance's outgoing interfaces and source IP address for VPN:
1. In the
Link Selection
>
Outgoing interface selection
section, select a method to specify the outgoing
interface:
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According to the routing table
– The OS's routing table finds the interface link with the lowest
metric (highest priority) through which to send traffic based on the remote site's IP addresses.
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Route based probing
– This method also consults the routing table for the link with the lowest
metric. But, before choosing an interface link to send traffic, all routing possibilities are
examined. This is to make sure that the link is active. The gateway selects the best match
(highest prefix length) active route with the lowest metric (highest priority). This method is
recommended when there is more than one external interface.
2. In the
Source IP address selection
section, select an option to configure the source IP address used
by the Security Gateway, when it initiates or responds to VPN traffic. This IP address is normally used
by the remote sites to connect to this Security Gateway:
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Automatically chosen according to outgoing interface
.
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Manually configured
– Enter an IP address that is always used as the source IP address of a
VPN tunnel.