Citrix Virtual Apps and Desktops

Host to client redirection

Host to client redirection allows URLs, embedded as hyperlinks in applications running on a Citrix session, to open using the corresponding application on the user endpoint device. Some common use cases for host to client redirection include:

  • Redirection of websites in cases where the Citrix server doesn’t have Internet or network access to the source.
  • Redirection of websites when running a web browser inside the Citrix session is not desired for security, performance, compatibility, or scalability reasons.
  • Redirection of specific URL types in cases where the required applications to open the URL are not installed on the Citrix server.

Host to client redirection is not intended for URLs that you access on a webpage or type in the address bar of the web browser running in the Citrix session. For redirection of URLs in web browsers, see Bidirectional URL redirection or Browser content redirection.

System requirements

  • Multi-session OS VDA
  • Supported clients:
    • Citrix Workspace app for Windows
    • Citrix Workspace app for Mac
    • Citrix Workspace app for Linux
    • Citrix Workspace app for HTML5
    • Citrix Workspace app for Chrome

The client device must have an application installed and configured for handling the redirection of the URL types.

Configuration

Use the Host to client redirection Citrix policy to enable this functionality. Host to client redirection is disabled by default. After you enable the Host to client redirection policy, the Citrix Launcher application registers with the Windows server to ensure that it can intercept URLs and send them to the client device.

Then you must configure the Windows Group Policy to use Citrix Launcher as the default application for the required URL types. On the Citrix server VDA, create the ServerFTAdefaultPolicy.xml file and insert the following XML code.

<?xml version="1.0" encoding="UTF-8"?>

<DefaultAssociations>

<Association Identifier="http" ProgId="ServerFTAHTML" ApplicationName="ServerFTA" />

<Association Identifier="https" ProgId="ServerFTAHTML" ApplicationName="ServerFTA" />

</DefaultAssociations>

From the Group Policy management console, go to Computer configuration > Administrative Templates > Windows Components > File Explorer > Set a default associations configuration file, and save your ServerFTAdefaultPolicy.xml file.

Note:

If a Citrix server doesn’t have the Group Policy settings, Windows prompts users to select an application for opening URLs.

By default, we support redirection of the following URL types:

  • HTTP
  • HTTPS
  • RTSP
  • RTSPU
  • PNM
  • MMS

To include additional standard or custom URL types on the list for redirection, create a new Association Identifier line in the ServerFTAdefaultPolicy.xml file referenced earlier. For example:

<Association Identifier="ftp" ProgId="ServerFTAHTML" ApplicationName="ServerFTA" />

<Association Identifier="mailto" ProgId="ServerFTAHTML" ApplicationName="ServerFTA" />

<Association Identifier="customtype1" ProgId="ServerFTAHTML" ApplicationName="ServerFTA" />

<Association Identifier="customtype2" ProgId="ServerFTAHTML" ApplicationName="ServerFTA" />

Adding URL types to the list also requires client configuration. Create the following registry key and values on the Windows client.

Note:

Editing the registry incorrectly can cause serious problems that might require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

  • Key: HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Policies\Citrix\ICA Client\SFTA
  • Value name: ExtraURLProtocols
  • Value type: REG_SZ
  • Value data: Specify the required URL types separated by semicolon. Include everything before the authority portion of the URL. For example: ftp://;mailto:;customtype1://;custometype2://

You can add URL types only for Windows clients. Clients missing the registry settings above reject redirection back to the Citrix session. Client must have an application installed and configured to handle the specified URL types.

To remove URL types from the default redirection list, create the following registry key and values on the server VDA.

  • Key: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Citrix\SFTA

  • Value name: DisableServerFTA
  • Value type: DWORD
  • Value data: 1

  • Value name: NoRedirectClasses
  • Value type: REG_MULTI_SZ
  • Value data: Specify any combination of the values: http, https, rtsp, rtspu, pnm, or mms. Type multiple values on separate lines. For example:

http

https

rtsp

To enable host to client redirection for a specific set of websites, create a registry key and values on the server VDA.

  • Key: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Citrix\SFTA
  • Value name: ValidSites
  • Value type: REG_MULTI_SZ
  • Value data: Specify any combination of fully qualified domain names (FQDNs). Type multiple FQDNs on separate lines. Include the FQDN only, without protocols (http:// or https://). An FQDN can include an asterisk (*) as a wildcard character in the leftmost position only. This wildcard matches a single level of domain, which is consistent with the rules in RFC 6125. For example:

www.exmaple.com

*.example.com

Note:

You cannot use the ValidSites key in combination with the DisableServerFTA and NoRedirectClasses keys.

Server VDA default browser configuration

Enabling host to client redirection as referenced in this section supersedes any previous default browser configuration on the server VDA. If a web URL is not redirected, the Citrix Launcher passes the URL to the browser configured in the command_backup registry key. The key points to Internet Explorer by default, but you can modify it to include the path to a different browser. For more information, see Server VDA default browser configuration in the list of features managed through the registry.

Host to client redirection