Link Aggregation - D-Link NetDefendOS User Manual

Chapter 3: Fundamentals
Default: 10
IfaceMon_MinInterval
Minimum interval between two resets of the same interface.
Default: 30
IfaceMon_RxErrorPerc
Percentage of errors in received packets at which to declare a problem.
Default: 20
IfaceMon_TxErrorPerc
Percentage of errors in sent packets at which to declare a problem.
Default: 7

3.4.3. Link Aggregation

Introduction
Where individual physical Ethernet interfaces of a NetDefend Firewall cannot provide the
bandwidth required for a specific stream of traffic, it is possible to use the NetDefendOS Link
Aggregation feature to combine two or more physical interfaces together so they act as one
logical NetDefendOS interface. This feature is sometimes referred to by other security product
vendors using names such as Link Bundling or NIC Teaming.
An Example Use Case
An example use case is where a NetDefend Firewall might only have multiple one Gigabit
Ethernet interfaces but the requirement for a particular traffic flow is bandwidth of three
Gigabits. A logical Link Aggregation object could then be created which combines the capacities
of three physical interfaces. This object can then be used in the NetDefendOS configuration like
any other interface and can be part of the Route and the IPRule or IPPolicy objects that govern the
traffic flow. NetDefendOS will then automatically spread the traffic between the physical
interfaces.
The diagram below shows a typical scenario where three 1Gb networks need to communicate
with a 10Gb network backbone through a firewall which only has 1 Gb interfaces. Three of the
firewall's 1Gb interfaces are connected to an external switch and grouped into a Link Aggregation
configuration object. The switch then provides the 10Gb link to the backbone.
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