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C. LoadMaster Network Topologies
1. One-Armed Balancer
If a one-armed configuration is selected then the following is true:
Only the eth0 Ethernet interface will be used (for both in and outbound traffic)
Real Servers and Virtual Services will be part of the same logical network – sometimes called flat-
based - this implies that both have public IP addresses if used for services within the Internet.
S-NAT does not make sense for one-armed configurations.
Does not automatically imply the use of Direct Server Return (DSR) methods on the Real Servers
Implies the clients (consumers of the service hosted by the LoadMaster) are on a logically separate
network to the LoadMaster and its’ Virtual Services (this is not true if used in conjunction with DSR).
2. Two-Armed and Multi-Armed Balancer
If a two-armed or Multi-Armed configuration is selected, then the following is true:
Both eth0 (net side) and eth1 (farm side) interfaces are used. Additional ports go to the farm side for
Multi-Armed configurations
Implies that the LoadMaster (eth0) and server farm(s) are on separate logical networks, sometimes
referred to as a NAT based topology.
The server farm(s) may make use of non-routable IP addresses
S-NAT may be useful in such a configuration
Clients may be on the same logical network as the LoadMaster
