How to setup IP Spoofing on a LoadRunner Injector

Projects should be aware if their application system under test will require LoadRunner Virtual Users to use IP Spoofing, and will be required to identify the number of additional IP addresses required to support their performance testing. Examples of need for IP Spoofing are where multiple web servers are load balanced, or where smart routers are used as gateways. If IP Spoofing is not used then, as source traffic appears to start from one IP address, traffic will only be routed to one server in a load balanced pair. A smart router may also determine that a constant stream of traffic from a single IP sources address is actually a DDoS attack, and will then terminate the port connections.

Note that multiple static IP Addresses are only required to be set-up on LoadRunner servers acting as Vuser Generators, and are not required on servers running purely as LoadRunner Controllers.

IP addresses must be allocated to the LoadRunner servers by Infrastructure Environments Delivery (IED), and must not be in use by any other servers. The number required for each server will depend on the application and test environment. All IP address allocation must be with static IP addresses, and should not use DHCP allocation.

Additional static IP addresses can be added to the LoadRunner Vuser Generators in two ways.

Option one, involves manually adding each static IP address to the appropriate network card through the network control panel.

Option two can only be used when contiguous blocks of static IP addresses are available to be added. In this case LoadRunner has an IP Wizard which takes the start IP address, and the total IP addresses required as parameters, which will then automatically set-up the required addresses. Not that a server restart is recommended after static IP addresses have been added to the server.