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In the above example, an FTP server (IP_192.168.2.2) and an HTTP server
(IP_192.168.2.3) are connected to the Internet via WAN1 (IP_200.200.200.1) and
WAN2 (IP_100.100.100.1) on BiGuard 30. Remote PCs are attempting to access the
servers via the Internet by making a DNS request, entering a URL
(www.mydomain.com). Using a load balancing algorithm, BiGuard 30 can direct
incoming requests to either WAN port based on the amount of load each WAN port
is currently experiencing. If WAN2 is experiencing a heavy load, BiGuard 30
responds to incoming DNS requests with WAN1. By balancing the load between
WAN1 and WAN2, your BiGuard 30 can ensure that inbound traffic is efficiently
handled, making sure that both ports are equally sharing the load and preventing
situations where service is slow because one port is completely saturated by
inbound traffic.
Please refer to appendix H for example settings.
A typical scenario of how traffic is directed with DNS Inbound Load Balancing is
illustrated below:
Built-in DNS
192.168.2.2
192.168.2.3
FTP
HTTP
200.200.200.1
www.mydomain.com
200.200.200.1
Authoritative Domain Name Server
100.100.100.1
100.100.100.1
DNS Request
DNS Reply
Built-in DNS
192.168.2.2
192.168.2.3
FTP
HTTP
www.mydomain.com
DNS Request
DNS Reply
Heav
y
load on WAN
2
Heav
y
load on WAN 1
200.200.200.1
100.100.100.1
WAN 1
WAN 2
WAN 1
WAN 2