When the NetScaler appliance communicates with the physical servers or peer devices, by default, it uses one of its own IP addresses as the source IP. The appliance maintains a pool of mapped IP addresses (MIPs) and subnet IP addresses (SNIPs), and selects an IP address from this pool to use as the source IP address for a connection to the physical server. The decision of whether to select a MIP or a SNIP depends on the subnet in which the physical server resides.
Enable Use Source IP mode (USIP) mode if you want NetScaler to use the client's IP address for communication with the servers. By default, USIP mode is disabled. USIP mode can be enabled globally on the NetScaler or on a specific service. If you enable it globally, USIP is enabled by default for all subsequently created services. If you enable USIP for a specific service, the client's IP address is used only for the traffic directed to that service.
As an alternative to USIP mode, you have the option of inserting the client's IP address (CIP) in the request header of the server-side connection for an application server that needs the client's IP address.
In the later NetScaler releases , if USIP is enabled, the default is to use a proxy port for server-side connections and not reuse connections. Not reusing connections may not affect the speed of establishing connections.
By default, the Use Proxy Port option is enabled if the USIP mode is enabled.
For more information about the Use Proxy Port option, see "Using the Client Port When Connecting to the Server."
The following figure shows how the NetScaler uses IP addresses in USIP mode.
At the command prompt, type one of the following commands:
At the command prompt, type:
set service Service-HTTP-1 -usip YES