D-Link 210 User Manual
Figure 4.7. A Route Load Balancing Scenario
We first need to define two routes to these two ISPs in the main routing table as shown below:
Route No.
Interface
Destination
Gateway
Metric
1
WAN1
all-nets
GW1
100
2
WAN2
all-nets
GW2
100
We will not use the spillover algorithm in this example so the routing metric for both routes should
be the same, in this case a value of 100 is selected.
be the same, in this case a value of 100 is selected.
By using the Destination RLB algorithm we can ensure that clients communicate with a particular
server using the same route and therefore the same source IP address. If NAT was being used for the
client communication, the IP address seen by the server would be WAN1 or WAN2.
server using the same route and therefore the same source IP address. If NAT was being used for the
client communication, the IP address seen by the server would be WAN1 or WAN2.
In order to flow, any traffic requires both a route and an allowing IP rule. The following rules will
allow traffic to flow to either ISP and will NAT the traffic using the external IP addresses of
interfaces WAN1 and WAN2.
allow traffic to flow to either ISP and will NAT the traffic using the external IP addresses of
interfaces WAN1 and WAN2.
Rule No.
Action
Src Interface
Src Network
Dest Interace Dest Network
Service
1
NAT
lan
lannet
WAN1
all-nets
All
1
NAT
lan
lannet
WAN2
all-nets
All
The service All is used in the above IP rules but this should be further refined to a service or service
group that covers all the traffic that will be allowed to flow.
group that covers all the traffic that will be allowed to flow.
Example 4.6. Setting Up RLB
4.4. Route Load Balancing
Chapter 4. Routing
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