Transparency pertains to how LoadMaster forwards traffic to real servers. In transparent mode, LoadMaster will pass along the original client's IP as the source IP. In non-transparent mode, LoadMaster will NAT the requests to the real server with LoadMaster's virtual service address. In order for your server to see the original sender's IP, you will need to operate transparently.
Transparency can be turned on for Layer 7 services and is always on for Layer 4 services. However, there are some obstacles to services functioning correctly in transparent mode. In order for transparent operation to work correctly, traffic must return through LoadMaster when returning from the servers. Typically this is done by setting the servers’ default gateway to LoadMaster.
However, challenges arise when the client and server are on the same subnet. In this case transparency cannot not work since the server will respond to the client directly. If you are in a situation where the clients and server are on the same subnet and you must have transparency, we recommend migrating to a two-armed configuration. This can be done by creating an additional subnet connected to LoadMaster and moving your servers there. With LoadMaster as a gateway for the servers, you will be able to operate transparently.
The biggest thing to remember when attempting to operate transparently is that the servers' gateway must be set to LoadMaster. If that is set properly, you can enable transparency by checking the 'L7 Transparency' checkbox under 'Basic Settings.