Citrix Access on SonicWALL SSL VPN Document Scope

This document describes how to configure and use Citrix bookmarks to access Citrix through SonicWALL  SRA 6.0. It also includes information about configuring relevant settings on a Citrix server. This document contains the following sections: •

“Feature Overview” section on page 1

•

“Administrator Tasks for Configuring Citrix Access” section on page 4

•

“User Tasks for Configuring Citrix Access” section on page 22

•

“Technical FAQs” section on page 27

•

“Glossary” section on page 28

Feature Overview This section provides an introduction to accessing Citrix through the SonicWALL SRA appliance using Citrix bookmarks. This section contains the following subsections: •

“What are Citrix Bookmarks?” section on page 2

•

“Benefits of Citrix Bookmarks” section on page 2

•

“Accessing Citrix Applications via SSL VPN” section on page 2

•

“Supported Platforms” section on page 3

Citrix Access on SonicWALL SSL VPN

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Feature Overview

What are Citrix Bookmarks? The SonicWALL SRA appliance uses bookmarks to access Citrix services, which are supported as a third-party application running on a separate server. Citrix is a remote access, application sharing service, similar to Terminal Services such as RDP. It employs an application virtualization technology, in which an application is hosted on a central server. There are many management capabilities over a Citrix deployment such as allocation of priority and a minimum set of resources to certain users, and data synchronization between different server farms. Citrix uses the ICA protocol to communicate with the client. The Citrix ICA Client is now renamed as the Citrix XenApp Web plug-in. With the Citrix XenApp Web plug-in, users can access Windows applications as a service available from anywhere.

Benefits of Citrix Bookmarks Using the SonicWALL SRA appliance to access Citrix provides the following benefits: •

Secure access – The SonicWALL SRA appliance provides secure access from anywhere.

•

Granular Control – Bookmarks, access policies, and other SSL VPN features provide full access control.

•

Strong Authentication – The SonicWALL SRA appliance supports various strong authentication methods which provides an added layer of security to your Citrix applications.

•

Consolidated access – The SonicWALL SRA appliance Virtual Office portal can provide multiple Citrix bookmarks from a single location.

Some of the benefits of using Citrix to virtualize applications are the following: •

Reduces the expense of individual application licenses for each user. You can purchase one copy of the application for your Citrix server along with a limited number of access licenses. When the client access limit is reached, clients must wait to connect to the Citrix server.

•

Facilitates auditing and reporting. You can track who uses which applications and when they are accessed.

•

CPU-intensive applications can run on a powerful Citrix server, allowing access by less-powerful clients.

•

Operating system and file system security may be better on a Citrix server than on client systems or systems accessed with RDP.

•

Citrix provides load balancing.

•

Citrix can act as a Web gateway providing comprehensive access policies.

Accessing Citrix Applications via SSL VPN There are two ways to use Citrix that are supported by the SonicWALL SRA appliance: •

The agent or client behaves seamlessly, accessing the application on the Citrix server as soon as the user logs into the client. This method is supported by the SonicWALL SRA appliance NetExtender.

•

The user accesses the application on the remote Citrix server through a Web interface. SonicWALL  SSL VPN Bookmarks support this access method.

The SonicWALL SRA appliance provides secure remote Citrix access in a fashion similar to Remote Desktop access. This provides a subset of Citrix functionality, since it does not support Program Neighborhood functionality, but is sufficient for access to any Citrix application or desktop.

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Citrix Access on SonicWALL SSL VPN

Feature Overview

Citrix can be compared to applications that use the Remote Desktop Protocol (RDP), in that both allow clients to access remote systems or servers. The fundamental difference is that RDP provides terminal session access control with access to the remote desktop itself, including the C drive and system files, whereas with Citrix, client access is usually restricted to application level access. Access to the Citrix desktops and applications requires installation of client software, although this software ranges from a full stand alone client fully integrated into Windows (Start Menu, Context menus) to a lightweight installation of an ActiveX control or a download of a Java applet. Citrix servers and applications are accessible through the Citrix NFuse portal. Access to the NFuse portal is provided by the SonicWALL SRA appliance HTTP(S) reverse proxy feature. After configuring the Citrix server, the SRA appliance administrator creates one or more Citrix (reverse proxy) bookmarks for use by client users. Client users initiate a Citrix session by first logging into the SonicWALL SRA appliance Virtual Office portal and then clicking on the Citrix bookmarks to the NFuse server. After authenticating with the NFuse portal, the user will see the Citrix applications and desktops that are accessible to him/her. This interface is provided by the Citrix server, but is reverse-proxied by the SRA appliance. When the user clicks on an application icon, Internet Explorer launches an ActiveX control similar to the one used by Remote Desktop, while other browsers use the Java version which launches an applet. Citrix support requires Internet connectivity in order to download the ActiveX client or the Java applet from the Citrix Web site. The server will automatically decide which Citrix client version to use. Citrix is accessed from Internet Explorer using ActiveX by default, or from other browsers using Java. Java can be used with Internet Explorer by selecting an option in the bookmark configuration in the SonicWALL SRA appliance. For Citrix access using Java, the Java applet download uses HTTP which is likely to have outbound access based on usual firewall deployments. When using the Java applet, the local printers are available in the Citrix client. However, under some circumstances it might be necessary to change the Universal Printer Driver to PCL mode.

Supported Platforms Citrix access is supported with the SonicWALL SRA appliance 6.0 on SonicWALL SRA 4200 and 1200 appliances, and on the SRA Virtual Appliance. Citrix access is also supported on previous releases of the SonicWALL SRA appliance. Citrix bookmarks with ActiveX and Java applet Citrix support are available on the SonicWALL SRA appliance 2.0 or newer for the SSL-VPN 2000 and 4000 appliances, and on the SonicWALL SRA appliance 3.5 and newer for the SRA 4200, 1200, and Virtual Appliance. Citrix IPv6 is supported on the SonicWALL SRA appliance 3.5 and higher. NTLM/Windows Integrated authentication is supported if it is enabled on the Citrix server. Some Citrix installations use NTLM instead of a login form to authenticate the user into the Web interface.

Note

Single Sign-On is not supported for Web Interface authentication or within the Citrix session. On the SonicWALL SRA appliance 6.0, Citrix Portal Bookmarks have been tested and verified to support the following Citrix Application Virtualization platforms through the Citrix Web Interface: Servers: •

XenApp Server 6.0

•

XenApp Server 5.0

•

XenApp Server 4.5

•

Presentation Server 4.0

•

MetaFrameXP Feature Release 3

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Administrator Tasks for Configuring Citrix Access

Clients: •

Receiver for Windows 3.0

•

Receiver for Java 10.1

•

XenApp Web Plug-in version 12.0.3 or earlier

•

Java client version 10.0 or earlier

Citrix client software is available as an ActiveX plugin (for Internet Explorer only) or a Java plugin. The Citrix ActiveX client is supported on systems running Windows XP with Internet Explorer 6.0 or higher. The Java plugin can be used with Internet Explorer, Firefox, Chrome, or Safari browsers on Windows, 7 Windows XP, Vista, Linux, or Mac OS client systems as noted in Table 1. For browsers requiring Java to run Citrix, you must have Sun Java 1.6.0_10 or above. Table 1

Citrix (Java 1.6.0_10+) Client - Supported Browsers per OS

Windows 7

Windows Vista

Windows XP

Internet Explorer

8.0 or higher

7.0 or higher

6.0 or higher

Firefox

4.0 or higher

4.0 or higher

4.0 or higher

Chrome

5.0 or higher

5.0 or higher

5.0 or higher

Linux

4.0 or higher 4.0 or higher

Safari

Note

Mac OS X

2 or 3

Citrix MetaFrame supports FireFox, Chrome, and Internet Explorer 7.x or earlier.

Administrator Tasks for Configuring Citrix Access This section contains the following subsections:

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•

“Deployment Scenario” section on page 5

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“Assumptions and Dependencies” section on page 5

•

“Configuring Authentication on the Citrix Server” section on page 6

•

“Creating a Citrix Access Policy” section on page 13

•

“Creating a Citrix Bookmark” section on page 15

•

“Enabling Custom URLs for Citrix Client Downloads” section on page 16

•

“Configuring the Web Interface on the Citrix Server” section on page 19

•

“Editing a Citrix Bookmark” section on page 20

Citrix Access on SonicWALL SSL VPN

Administrator Tasks for Configuring Citrix Access

Deployment Scenario The recommended deployment scenario for Citrix environments places the Citrix server(s) on the LAN behind a SonicWALL Unified Threat Management (UTM) appliance acting as the gateway firewall. A SonicWALL SRA 4200 appliance is connected to a firewall interface in the DMZ. Traffic passing between the SRA and the LAN passes through the UTM appliance where it is examined for threats.

SonicWALL UTM Firewall X1

PRO 5060

X0

X2

Switch

Switch

Router

DMZ Remote Users

LAN X0

Secure Remote Access

Citrix Servers

SRA 4200

SRA 4200

Internet Zone Apps, Email, AD, SQL

Assumptions and Dependencies •

The administrator must have the Citrix Web Interface installed and functioning for the Citrix installation.

•

Microsoft Loopback hotfix (KB884020) is required, although this can be avoided if the ActiveX control does not use loopbacks higher than 127.0.0.1.

•

ActiveX: Users must have enough privileges in order to be able to install an ActiveX control if they don’t already have one installed.

•

Java: JRE 1.6.0_10 and above is required by the Citrix Java client in the SonicWALL SRA appliance 6.0. If a lower version is detected, the connection is refused and the user is advised to upgrade Java.

•

ActiveX & Java: Firewall rules must allow for Internet Explorer and for the JRE to be able to open server sockets on the system.

•

Java: The SonicWALL SRA appliance must have a DNS server set up (critical).

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Administrator Tasks for Configuring Citrix Access

Configuring Authentication on the Citrix Server You can configure the Citrix server for anonymous or authenticated access. If you select anonymous access, you can configure the Citrix server for explicit, or forms-based, authentication to make sure that there is at least some type of authentication available for users. See the following sections: •

“Configuring Anonymous or Authenticated Access” on page 6

•

“Configuring Explicit Authentication on the Citrix Server” on page 10

Configuring Anonymous or Authenticated Access Microsoft IIS Manager must be configured on the Citrix server to enable anonymous access for Citrix. When Windows Integrated Authentication is configured on IIS and the Citrix server is accessed by a client through the SonicWALL SRA appliance, the SRA appliance will display a message indicating that it does not support the HTTPS authentication scheme used by Citrix.

To configure authentication for Citrix access through the SonicWALL SRA appliance, perform the following steps: Step 1

6

On the Citrix server (a Windows Server system), click Start > All Programs.

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Administrator Tasks for Configuring Citrix Access

Step 2

Select Administrative Tools > Internet Information Services (IIS) Manager.

Step 3

In the Internet Information Services (IIS) Manager window, expand the entries for the local computer, Web Sites, Default Web Site, and Citrix.

Step 4

Under Citrix, right-click the service name, for example XenApp, and select Properties from the right-click menu.

Step 5

In the Properties window, click the Directory Security tab.

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Administrator Tasks for Configuring Citrix Access

Step 6

Under Authentication and access control, click Edit.

Step 7

For anonymous access to the Citrix server, select the Enable anonymous access check box in the Authentication Methods window. (To configure authenticated access, skip to Step 12.)

Step 8

In the User name field, type in the account name to be used for anonymous access or click Browse to select it from the account list.

Step 9

In the Password field, type in the password for this account.

Step 10 Click OK.

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Administrator Tasks for Configuring Citrix Access

Step 11 An IIS Manager dialog box warns that the anonymous authentication option will result in unencrypted

passwords being transmitted over the network except when HTTPS or SSL connections are used. Since we are using HTTPS/SSL in this case, you can safely click Yes to continue.

Step 12 To configure authenticated access to the Citrix server rather than anonymous access as described above,

clear the Enable anonymous access check box in the Authentication Methods window. Step 13 Under Authenticated access, select the Basic authentication (password is sent in clear text) check box.

Step 14 Click OK.

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Administrator Tasks for Configuring Citrix Access

Configuring Explicit Authentication on the Citrix Server Explicit, or forms-based, authentication is used in conjunction with the anonymous access setting on Microsoft IIS to provide some form of authentication for users. The administrator selects the Explicit authentication method on the Citrix server, if it is not already selected. If only anonymous authentication is configured, Citrix may automatically detect it and force Explicit authentication, which will present a login form to the user. Explicit authentication performs the necessary encryption. To configure explicit authentication on the Citrix server, perform the following steps:

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Step 1

Log in to the Citrix server as the administrator, open the Start menu, and click Access Suite Console for Presentation Server.

Step 2

In the Citrix Web Interface Management window, select the XenApp URL, for example: http://CTX-EDU-1.csm.demo/Citrix/XenApp1.

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Administrator Tasks for Configuring Citrix Access

Step 3

In the right pane under Edit Settings, click Authentication Methods. and then select the Explicit check box in the Configure Authentication Methods window.

Step 4

Select the desired settings for Enforce 2-factor authentication and Allow user to change password.

Step 5

Click Next.

Step 6

For the Authentication Type step, select the Windows or NIS (UNIX) radio button.

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Administrator Tasks for Configuring Citrix Access

Step 7

Click Next.

Step 8

For the Specify Authentication Type Settings step, under Domains, select the Display Domain field radio button.

Step 9

Click the Add button and add your domain, if necessary.

Step 10 Select Selection in the Optionally, specify domains for drop-down list, and select your domain.

Step 11 Click Next.

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Administrator Tasks for Configuring Citrix Access

Step 12 For the Check Summary step, verify your settings and then click Finish.

Creating a Citrix Access Policy You can configure access policies on the SonicWALL SRA appliance to provide different levels of access to the Citrix server. There are three levels of access policies: global, group, and user. You can deny or permit access to the Citrix server by creating access policies for a Citrix server IP address, an IP address range (for a server farm), or a network object. User policies take precedence over group policies and group policies take precedence over global policies, regardless of the policy definition. For policies at the same level, the most specific policy takes precedence.

Tip

When using Citrix bookmarks, in order to restrict proxy access to a host, a Deny rule must be configured for both Citrix and HTTP services. For more information about access policies, including policy hierarchy rules, see the “Users Configuration” chapter in the SonicWALL SRA Administrator’s Guide. The procedure is the same for configuring user, group, or global access policies, except for the initial page (Users > Local Users or Users > Local Groups) and the selection of either a user, a group, or the global option for which to configure the policy. To configure an access policy for a user, perform the following steps:

Step 1

In the SonicWALL SRA appliance management interface, navigate to Users > Local Users (or Users > Local Groups).

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Administrator Tasks for Configuring Citrix Access

Step 2

Click the configure icon next to the user (or group or Global Policies) that you want to configure.

Step 3

In the Edit User Settings window, select the Policies tab.

Step 4

Click Add Policy...to display the Add Policy window.

Step 5

In the Add Policy window, in the Apply Policy To drop-down list, select whether the policy will be applied to an individual host, a range of addresses, or a network object. You can also select an IPv6 host or a range of IPv6 addresses. The Add Policy dialog box changes depending on what type of object you select in the Apply Policy To drop-down list.

Note

Step 6

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The SonicWALL SRA appliance policies apply to the destination address(es) of the SonicWALL SRA appliance connection (the Citrix server), not the source address. You cannot permit or block a specific IP address on the Internet from authenticating to the SonicWALL SRA appliance gateway with a policy created on the Policies tab. However, it is possible to control source logins by IP address with a login policy created on the user's Login Policies tab. Type a descriptive name into the Policy Name field.

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Administrator Tasks for Configuring Citrix Access

Step 7

Step 8

Note

Step 9

Do one of the following, depending on your selection in the Apply Policy To field: •

Type an IP address in the IP Address field.

•

Type a starting IP address in the IP Network Address field and type a subnet mask value in the Subnet Mask field in the form 255.255.255.0.

•

Select the network object from the Network Object drop-down list. The port number is included in the network object definition.

In the Port Range/Port Number field, optionally enter a port range or an individual port.

The Citrix Web interface and Citrix ICA server listen on different ports, typically 80/443 and 1494 respectively, which are both needed for a Citrix session. When creating a port-based access policy, you will need to create two policies in order to specify both ports. Standard TCP ports used by Citrix are mentioned in the knowledge base article available at: http://support.citrix.com/article/CTX101810 In the Service drop-down list, optionally select one of the following: •

Citrix Portal (Citrix) – Select this if the Citrix bookmark uses HTTP

•

Citrix Portal (Citrix_https) – Select this if the Citrix bookmark uses HTTPS

If the Citrix server can be accessed using either HTTP and HTTPS, then you may need to create two access policies, one for each service. An IP address based policy may be simpler in this case. Step 10 In the Status drop-down list, click on an access action, either ALLOW or DENY. Step 11 Click Accept.

Creating a Citrix Bookmark You can configure a Citrix bookmark for a user or for a group. The procedure is the same, except for the initial page (Users > Local Users or Users > Local Groups) and the selection of either a user or a group for which to configure the bookmark. To configure a Citrix bookmark for a user, perform the following steps: Step 1

In the SonicWALL SRA appliance management interface, navigate to Users > Local Users.

Step 2

Click the configure icon next to the user you want to configure.

Step 3

In the Edit User Settings window, select the Bookmarks tab.

Step 4

Click Add Bookmark...

Step 5

Enter a descriptive name for the bookmark in the Bookmark Name field.

Step 6

Enter the name or IP address of the bookmark in the Name or IP Address field.

Note

A Citrix bookmark will accept a port option with the IP address (IP_address:portnum).

Step 7

From the Service drop-down list, select Citrix Portal (Citrix). The display will change.

Step 8

To enable SSL encryption for communication between the SRA appliance and the Citrix server, select the HTTPS Mode check box.

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Administrator Tasks for Configuring Citrix Access

Step 9

Optionally select the Always use Java in Internet Explorer checkbox to use Java to access the Citrix Portal when using Internet Explorer. Without this setting, a Citrix ActiveX client or plugin must be used with IE. This setting lets users avoid installing a Citrix client or plugin specifically for IE browsers. Java is used with Citrix by default on other browsers and also works with Internet Explorer. Enabling this check box leverages this portability. When using the Java applet, the local printers are available in the Citrix client. However, under some circumstances it might be necessary to change the Universal Printer Driver to PCL mode.

Step 10 To explicitly set the Citrix ICA server address for the Citrix ICA session, select the Always use specified

Citrix ICA Server checkbox and then type the server IP address into the ICA Server Address field. Some Citrix deployments have the Citrix Web Interface on one IP address and the ICA server listening on a different address. If the Citrix Web Interface and Citrix ICA server do not share the same IP address, use this setting to explicitly set the ICA server address. Step 11 Click Add.

Enabling Custom URLs for Citrix Client Downloads The Services > Settings page allows the administrator to configure custom URLs for Citrix Java or ActiveX client downloads.

The administrator needs to host the clients on a local Web server so they are available for download at the indicated URLs. See the following sections:

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•

“Hosting the Citrix Clients on a Local Web Server” on page 17

•

“Configuring Custom URLs on Services > Settings” on page 19

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Administrator Tasks for Configuring Citrix Access

Hosting the Citrix Clients on a Local Web Server You can download the Citrix Java and ActiveX client packages from www.citrix.com, and place them on a local Web server to make them available to your users. To download the Citrix clients to your local Web server: Step 1

In a browser on your local Web server, navigate to the Downloads page for Receiver on www.citrix.com.

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Administrator Tasks for Configuring Citrix Access

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Step 2

To download the ActiveX Receiver client, click Receiver for Windows 3.2.

Step 3

In the Receiver for Windows 3.2 popup, click Download.

Step 4

To download the Java Receiver client, click Receiver for Java 10.1 on the Citrix Downloads page (shown in Step 1 on page 17.

Step 5

Click Download for either the .tar or the .zip package.

Step 6

In the Receiver for Java 10.1 popup, click Download.

Step 7

Move the files to the appropriate location on the Web server.

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Administrator Tasks for Configuring Citrix Access

Configuring Custom URLs on Services > Settings The administrator needs to host the Citrix clients on a local Web server and have the SRA download these clients from there. You can configure the URLs for the Citrix Java or ActiveX client downloads on the Services > Settings page.

To configure custom URLs for Citrix Java or ActiveX client downloads, perform the following steps: Step 1

In the SonicWALL SRA appliance management interface, navigate to the Services > Settings page

Step 2

Select the Enable custom URL for Citrix Java client downloads checkbox if you want your own HTTP URL to be used to download the Citrix Java client. Fill-in the custom URL in the URL field. If this option is not enabled, the default URL will be used. The default URL is shown in grey text in the URL field. The maximum length for the custom URL is 255 characters.

Step 3

Select the Enable custom URL for Citrix ActiveX client downloads checkbox if you want your own HTTP URL to be used to download the Citrix ActiveX client. Fill-in the custom URL in the URL field. If this option is not enabled, the default URL will be used. The default URL is shown in grey text in the URL field. The maximum length for the custom URL is 255 characters.

Step 4

Click Accept.

Configuring the Web Interface on the Citrix Server In the Citrix Web Interface, you can configure the Preferences to use the native client rather than the Java client. This prevents a possible error when the Java client is launched. To configure use of the native client: Step 1

Log in to the SSL VPN Virtual Office portal and click on a Citrix bookmark.

Step 2

Log in to the Citrix Web Interface.

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Administrator Tasks for Configuring Citrix Access

Step 3

Right-click the site name, such as “MetaFrame”, and select Client Deployment from the right-click menu.

Step 4

In the dialog box, select Native Client.

Step 5

Alternatively, configure this setting in the Preferences options. Select Connection Preferences.

Step 6

Select Native for the client.

Step 7

For Fallback Behavior, also select the Native client.

Editing a Citrix Bookmark You can edit an existing Citrix bookmark by clicking the edit icon on the Virtual Office page. To edit an existing Citrix bookmark, perform the following steps:

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Step 1

In the SonicWALL SRA appliance management interface, navigate to the Virtual Office page.

Step 2

Click Show Edit Controls to expose the Edit and Delete icons for each bookmark.

Step 3

Click the Edit icon for the bookmark you wish to edit.

Citrix Access on SonicWALL SSL VPN

Administrator Tasks for Configuring Citrix Access

Step 4

In the Edit Bookmark page, you can view information about the available settings.

Step 5

To make changes to the Bookmark Name, Name or IP Address, or Description fields, type in the new value(s).

Step 6

To change ability of users to edit the bookmark, select a new value from the Allow user to edit/delete drop-down list. The default is Use user policy.

Step 7

To set the default window size for Citrix sessions from the Edit Bookmark page, use the Resource Window Size drop-down list to select the desired window size, as explained in step 8 on page 27.

Step 8

To enable SSL encryption for communication between the SRA appliance and the Citrix server, select the HTTPS Mode check box.

Step 9

To force Internet Explorer to use the Citrix Java applet rather than the default ActiveX control, select the Always use Java in Internet Explorer check box. This setting lets users avoid installing a Citrix ICA client or MetaFrame Web plug-in specifically for Internet Explorer browsers. When using the Java applet, the local printers are available in the Citrix client. However, under some circumstances it might be necessary to change the Universal Printer Driver to PCL mode.

Step 10 To explicitly set the Citrix ICA server address for the Citrix ICA session, select the Always use specified

Citrix ICA Server checkbox and then type the server IP address into the ICA Server Address field. Some Citrix deployments have the Citrix Web Interface on one IP address and the ICA server listening on a different address. If the Citrix Web Interface and Citrix ICA server do not share the same IP address, use this setting to explicitly set the ICA server address. Step 11 Click OK.

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User Tasks for Configuring Citrix Access

User Tasks for Configuring Citrix Access Citrix is a remote access, application sharing service, similar to RDP. It enables users to remotely access files and applications on a central computer over a secure connection. Access to the Citrix server and its shared applications is provided with bookmarks on the SonicWALL SRA appliance Virtual Office portal. The administrator may have created either ActiveX or Java bookmarks. When the user launches a Citrix bookmark, the interaction is identical to reverse proxy browsing until an application icon is clicked. At that point a window containing an ActiveX control or a Java applet will pop up. Users might encounter several warnings and dialog boxes the first time they launch a Citrix application. The causes for these are certificate mismatches, applet security warnings, ActiveX security warnings, and pop-up blocking. For the ActiveX version to be functional, the Receiver for Windows 3.0 client or the MetaFrame Web plug-in (which was previously called Windows ICA client) must be installed on the client machine. If the client machine does not have a pre-installed Receiver, MetaFrame, or ICA client, then the ActiveX control invokes an installer that downloads the necessary plugin and prompts the user for installation. The user has to go through the installation process only once, and will not be prompted for installation again for future Citrix sessions. This step requires connectivity to www.citrix.com or to the custom URL of a configured local Web server from the SRA appliance. See the following sections for information about using ActiveX or Java bookmarks for Citrix access: •

“Using ActiveX Bookmarks” on page 22

•

“Using Java Bookmarks” on page 25

Using ActiveX Bookmarks When using Internet Explorer, Citrix bookmarks launch the ActiveX Citrix client. The following steps describe how to launch and use the ActiveX Citrix client to access applications on the Citrix server:

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Step 1

Using an Internet Explorer browser, log in to the SonicWALL SRA appliance Virtual Office portal where the Citrix bookmarks are available. Click on the Citrix bookmark. The first time you use a Citrix bookmark, it will download and install the Citrix Web Client on your computer if you do not already have it.

Step 2

Click Download to download the client software.

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User Tasks for Configuring Citrix Access

Step 3

If using Internet Explorer Security, click Allow to begin the download.

Step 4

To install XenApp software, open the downloaded file (default file name is XenAppWeb.exe).

Step 5

Wait for the Citrix Web Client to install.

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User Tasks for Configuring Citrix Access

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Step 6

Click Yes to the Citrix license agreement.

Step 7

When the Citrix Web Client has installed, click OK. If the Citrix Web Interface login window does not display, restart your Web browser and launch the Citrix bookmark again.

Step 8

Enter your username, password, and domain in the Citrix Web Interface login window.

Step 9

The Citrix Web Interface home page is displayed. Click on the application you want to use.

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User Tasks for Configuring Citrix Access

Step 10 You may be prompted to install additional Citrix software.

The shared application is now launched.

Using Java Bookmarks When using browsers other than Internet Explorer, Citrix bookmarks launch the Java Citrix client. You can also configure the SonicWALL SRA appliance to use the Java Citrix client even when Internet Explorer is the user’s browser. The following steps describe how to launch and use the Java Citrix client.

Note

For more detailed, current information on Citrix Systems configuration and use, see the Citrix Systems web site at www.citrix.com.

Step 1

Using any supported browser, log in to the SonicWALL SRA Virtual Office portal where the Citrix bookmarks are available. Click on the Citrix bookmark. The login window displays.

Step 2

For Logon type, select either Anonymous or Explicit. Select Anonymous to login without providing a user name. Note that you may not be able to access resources that require authentication. Select Explicit to login with a user name and password. You may also be required to provide a domain name or NDS context.

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User Tasks for Configuring Citrix Access

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Step 3

Click the Log On button. The Citrix Java applet displays. The default applications will display in the Applications section in the middle of the window.

Step 4

Click on the Citrix application to launch it.

Step 5

Click on Preferences to customize the Citrix Java applet settings.

Step 6

Select Display Settings to change the language and to specify if Citrix hints should be displayed.

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Technical FAQs

Step 7

Select Session Settings to customize the default window size for Citrix sessions.

Step 8

In the Window Size drop-down menu, select one of the following options:

Step 9

•

No preference: Uses the default setting configured by your administrator.

•

Full screen: Resources are maximized to fill your screen.

•

Seamless: Resources that support resizing appear in resizable windows.

•

Custom dimensions: Enables you to specify the width and height of the resource window in pixels.

•

Percentage of screen: Enables you to specify the percentage of your screen the resources will occupy.

Select Account Settings to configure the behavior of your sessions when you log out.

Step 10 Select the Log off all sessions checkbox to shut down all of your active resources when you log off from

the Citrix session. If you disable this checkbox, any active resources that are hosted on a remote server continue to run when you log off. (Offline applications always continue to run when you log off from the Citrix session.)

Technical FAQs How do I find more technical information about Citrix?

Technical information is available at the following links: •

http://www.citrix.com

•

http://en.wikipedia.org/wiki/Citrix

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Glossary

Glossary Basic Authentication – For Citrix bookmarks and other HTTP transactions, using basic authentication means that the client requests a Web page, the server responds with an authentication request, the user sees a popup login window and enters his or her credentials, the user name and password are encoded with the Base 64 algorithm (not for security, but rather to encode non-HTTP-compatible characters), the encoded credentials are appended to the Web page request and sent back to the server. Citrix – A product by Citrix Inc. that provides Terminal Services-like access to a server farm. This product allows desktop and application sharing, provides load balancing, Web gateway, and comprehensive access policies. For more detail, see http://www.citrix.com. Citrix ICA Client – ICA stands for Independent Computing Architecture. The Citrix ICA Client is the client software that was later replaced by the Citrix MetaFrame plug-in and Citrix MetaFrame Web plug-in. The Citrix Receiver client is the most recent client software. Citrix Receiver Client – Citrix Receiver is a lightweight software client available for Mac OS, Windows, Linux, iOS, iPhone, iPad, Android, BlackBerry, Windows Mobile, Chromebook, and other platforms. Users can access hosted applications on a Citrix server from any of these devices. Receiver for Windows 3.0 is used for Citrix ActiveX bookmarks, while Receiver for Java 10.1 is used for Citrix Java bookmarks. Citrix Web Interface – The Citrix Web Interface provides the SonicWALL SRA appliance users with access to MetaFrame Server applications and content through a standard Web browser. The Web Interface uses Java and .NET technology to dynamically create an HTML representation of server farms for MetaFrame Server sites. All applications published in the server farms can be made available and presented to users. The Citrix Web Interface also provides user access through the Program Neighborhood Agent, but this is not currently supported in the SonicWALL SRA appliance. ICA file – A configuration file that adheres to the INI format. This file is used to launch Citrix clients and contains all the options necessary for connection. Integrated Windows Authentication – Integrated Windows Authentication (IWA) is more secure than basic authentication, and can be selected when configuring Microsoft IIS. IWA is used in environments where users have Windows domain accounts and the applications in use are Active Directory aware. When using IWA, the user's domain logon credentials are encrypted and sent to the Web server with Web page requests. The Kerberos authentication protocol is used, or if unavailable, NTLMSSP is used. If the domain logon credentials cannot be used, the user is prompted to enter a user name and password. IWA cannot be used over an HTTP proxy server, but works with most modern browsers. It can also be used with file sharing, Windows service programs, and Microsoft SQL Server. Java Applet – A Java application that runs in a limited environment in the Web browser. Unlike ActiveX, it is platform independent. MetaFrame XP – MetaFrame XP runs on a server and allows multiple users to log on and run applications in separate, protected sessions. You install and publish the applications or other resources that you want to deploy. You can group a number of servers together to form a MetaFrame XP server farm that you manage as a single entity. NFuse – NFuse Classic is a Web-based application deployment system that provides users with access to MetaFrame and MetaFrame applications through a standard Web browser. Each user sees all the applications published in the Citrix server farm for that user. NFuse provides centralized application management and places complete control over the application deployment process in the hands of the administrator. NTLM – NT LAN Manager is a Microsoft authentication protocol similar to MS-CHAP. NTLM is used with the SMB protocol. The protocol uses a challenge-response sequence of three messages between a client that wishes to authenticate and the server that is requesting authentication.

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Glossary

Presentation Server – Presentation Server allows delivery of applications as a service, providing on-demand access to users. It provides application virtualization and application streaming delivery. Presentation Server runs on a server and allows multiple users to log on and run applications in separate, protected sessions. You install and publish the applications or other resources that you want to deploy. You can group a number of servers together to form a server farm that you manage as a single entity. Program Neighborhood Agent – Program Neighborhood Agent is a feature in Citrix MetaFrame/XenApp and Presentation Server products that allows applications to be assigned to users. The name was originally inspired by Windows “Network Neighborhood” and was changed to “Citrix Applications” in Citrix MetaFrame. The Program Neighborhood Agent client uses the Access Management Console and published application settings to provide centralized management of the client settings. It also provides pass-through authentication and integrates with the user's desktop and Start menu. It provides client to server content redirection, changing the local Windows File Type Association so that local files automatically launch the associated Citrix published application. Reverse Proxy – Such a proxy is deployed between a remote user outside the intranet and a target Web server within the intranet. The proxy intercepts packets flowing across it. XenApp Server – Citrix XenApp™ is the new name for Citrix Presentation Server. Citrix XenApp™ is an application virtualization solution. Virtualizing applications lets IT manage a single instance of each application in the data center. Applications can be run on high-powered servers in the data center for online access by remote clients, or delivered via application streaming directly to Windows PC’s. XenApp Plug-in – Users run the Citrix XenApp Plug-in on their client devices to access resources published on XenApp servers. The XenApp Plug-in requires the Citrix Web Interface. The Citrix XenApp Plug-in allows users to access published resources from a Windows desktop environment, including the Start menu and the Windows notification area, by icons that behave like local icons. The Citrix Receiver client is more recent than XenApp. XenApp Web Plug-in – Citrix XenApp Web Plug-in is a smaller plugin that can be installed from the XenAppWeb.msi or the XenAppWeb.exe file. Users access published resources by clicking links on a Web page you publish on your corporate intranet or the Internet.Solution Document Version History

Version Number

Date

Notes

1

4/19/2012

This document was created by Patricia Day.

P/N 232-002124-00 Rev A 5/2012

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