R3204P16-HP Load Balancing Module Load Balancing Configuration Guide-6PW101

5
Working mechanism of firewall load balancing
Figure 5 Network diagram for firewall load balancing
Firewall load balancing includes the following basic elements:
• Cluster: A cluster consists of LB devices and firewalls to provide network traffic load balancing.
• LB device: A device that distributes traffic from the request sender to multiple firewalls. LB devices fall
into level 1 LB devices and level 2 LB devices. In the above figure, if traffic is from Host A to Host B,
LB device A is level 1, and LB device B is level 2; if traffic is from Host B to Host A, LB Device B is level
1, and LB Device A is level 2.
• Firewall: A firewall filters packets.
Figure 6 Work flow of firewall load balancing
The following describes the work flow of firewall load balancing:
1. LB device A receives the traffic from the source.
2. LB device A forwards the traffic to a firewall based on the destination IP address range and the
pre-configured load balancing rules of the traffic.
3. The firewall forwards the traffic to LB device B.
(1) Traffic from source
LB device A
Firewall
(3) Forward
LB device B
(2)
Scheduler & Forward
(4) Record &
Forward to destination
(5) Traffic from destination
(7) Forward
(8) Forward to source
(6) Forward