System settings

Configuration of system settings includes basic tasks such as configuring HTTP ports to enable connection keep-alive and server offload, setting the maximum number of connections for each server, and setting the maximum number of requests per connection. You can enable client IP address insertion for situations in which a proxy IP address is not suitable, and you can change the HTTP cookie version.

You can also configure a Citrix ADC appliance to open FTP connections on a controlled range of ports instead of ephemeral ports for data connections. This improves security, because opening all ports on the firewall is insecure. You can set the range anywhere from 1,024 to 64,000.

Before deployment, go through the verification checklists to verify your configuration. To configure HTTP parameters and the FTP port range, use the Citrix ADC GUI.

You can modify the types of HTTP parameters described in the following table.

Parameter Type: HTTP Port Information

Specifies: The web server HTTP ports used by your managed servers. If you specify the ports, the appliance performs request switching for any client request that has a destination port matching a specified port.

Note: If an incoming client request is not destined for a service or a virtual server that is specifically configured on the appliance, the destination port in the request must match one of the globally configured HTTP ports. This allows the appliance to perform connection keep-alive and server off-load.

Parameter Type: Limits

Specifies: The maximum number of connections to each managed server, and the maximum number of requests sent over each connection. For example, if you set Max Connections to 500, and the appliance is managing three servers, it can open a maximum of 500 connections to each of the three servers. By default, the appliance can create an unlimited number of connections to any of the servers it manages. To specify an unlimited number of requests per connection, set Max Requests to 0.

Note: If you are using the Apache HTTP server, you must set Max Connections equal to the value of the MaxClients parameter in the Apache httpd.conf file. Setting this parameter is optional for other web servers.

Parameter Type: Client IP Insertion

Specifies: Enable/disable insertion of the client’s IP address into the HTTP request header. You can specify a name for the header field in the adjacent text box. When a web server managed by an appliance receives a subnet IP address, the server identifies it as the client’s IP address. Some applications need the client’s IP address for logging purposes or to dynamically determine the content to be served by the web server.

You can enable insertion of the actual client IP address into the HTTP header request sent from the client to one, some, or all servers managed by the appliance. You can then access the inserted address through a minor modification to the server (using an Apache module, ISAPI interface, or NSAPI interface).

Parameter Type: Cookie Version

Specifies: The HTTP cookie version to use when COOKIEINSERT persistence is configured on a virtual server. The default, version 0, is the most common type on the Internet. Alternatively, you can specify version 1.

Parameter Type: Requests/Responses

Specifies: Options for handling certain types of requests, and enable/disable logging of HTTP error responses.

Parameter Type: Server Header Insertion

Specifies: Insert a server header in Citrix ADC-generated HTTP responses.

To configure HTTP parameters by using the GUI, follow these steps:

  1. In the navigation pane, expand System, and then click Settings.
  2. In the details pane, under Settings, click Change HTTP parameters.
  3. In the Configure HTTP parameters dialog box, specify values for some or all of the parameters that appear under the headings listed in the table above.
  4. Click OK.

To set the FTP port range by using the GUI, follow these steps:

  1. In the navigation pane, expand System, and then click Settings
  2. In the details pane, under Settings, click Change global system settings.
  3. Under FTP Port Range, in the Start Port and End Port text boxes, type the lowest and highest port numbers, respectively, for the range you want to specify (for example, 5000 and 6000).
  4. Click OK.
System settings