Loa d Ba la nce r Conf ig ur at io n
Kernel IP routing table
Destination
10.1.0.0
default
Gateway
*
10.1.3.4
Genmask
255.255.0.0
Flags Metric Ref
U
0.0.0.0
0
UG
Use Iface
0
0
0 eth0
0
Load Balancer Configuration
The load balancer is configured with a virtual IP address of 1.2.3.4, and two real servers, WLSS
1 and WLSS 2, having addresses 10.1.1.1 and 10.1.1.2, respectively. The load balancer also has
an internal IP address of 10.1.3.4 configured on the 10.1/16 network. The UAC address, 2.3.4.5,
is reachable from the load balancer by static route configuration on the load balancer. The load
balancer routing table is shown in Listing 3-2.
Listing 3-2 Load balancer Routing Table
$ /sbin/route
Kernel IP routing table
Destination
Gateway
10.1.0.0 *
1.2.0.0 *
Genmask
255.255.0.0
255.255.0.0
Flags Metric Ref
U
0
U
Use Iface
0
0
0 eth1
0
Because the SIP protocol specification (RFC 3261) dictates the destination IP address and UDP
port numbers that user agents must use when sending requests or responses, the NAT
configuration of the load balancer must be done in a way that does not violate RFC 3261
requirements. Three setup options can be used to accomplish this configuration:
z NAT-based configuration
z maddr-Based Configuration
z rport-Based Configuration
The sections that follow describe each approach.
Configuring Network Resources
3-3