For an improved
performance in the delivery of virtual desktop applications, you can integrate
the NetScaler appliance with Citrix XenDesktop and use the NetScaler load
balancing feature to distribute the load across the Web Interface servers and
the Desktop Delivery Controller (DDC) servers.
Generally, you use
XenDesktop in situations where applications are not compatible with running on
a terminal server or XenApp, or if each virtual desktop has unique
requirements. In such cases, you need one desktop host for each user that
connects. However, the hosts can be pooled so that you need only one host for
each currently connected user.
application service deployed for XenDesktop is the Desktop Delivery Controller
(DDC). The DDC is installed on a server, and its main function is to register
desktop hosts and broker client connections to them.
The DDC also
authenticates users and manages the assembly of the users' virtual desktop
environments by controlling the state of the desktops, and starting and
stopping the desktops.
multiple DDCs are installed to enhance availability.
The Web Interface
servers provide secure access to virtual desktops. The Web Interface is the
initial connection portal to the Desktop Delivery Controller (DDC). The Web
browser on the user's device sends information to the Web server, which
communicates with the server farm to provide the user with access to the
figure shows the topology of a NetScaler appliance working with XenDesktop.
Note: Although you
can use the HTTP protocol, Citrix recommends that you use SSL for communication
between the client and the NetScaler. You can use the HTTP protocol for
communication between the NetScaler and the DDC servers even though you use the
SSL protocol for communication with the client.
A wizard is
available for configuring basic load balancing in a XenDesktop deployment. You
can use the wizard to configure Web interface servers and a virtual server for
them, and DDC servers and a virtual server for them. The virtual servers that
you configure are bound to services specified as Web Interface services and DDC
services. Each virtual server is configured with the default load balancing
method, and the default features are enabled. A monitor is created and bound to
each virtual server.
creates a basic setup, with default values for options such as the load
balancing method, policies, persistence, and advanced settings. You can change
any of the values if necessary.