This section contains tips on configuring applications and documents for use with SGD. This section includes the following topics:
Section 4.8.1, “Starting an Application or Desktop Session Without Displaying a Webtop”
Section 4.8.3, “Configuring Multiple Monitor Displays Without Using RANDR”
Section 4.8.4, “Improving the Performance of Windows Applications”
Section 4.8.5, “Improving the Performance of Java Desktop System Desktop Sessions or Applications”
Section 4.8.8, “Configuring Common Desktop Environment Applications”
With SGD, you can start a single application or a full-screen desktop session without displaying the webtop. You can do this in any of the following ways:
Use My Desktop – My Desktop enables users to log in and display an application without displaying a webtop. Typically this is used for full-screen desktop applications. See Section 4.5.8, “Using My Desktop” for details.
Use SGD web services – Develop you own application for starting a single application from a URL. You can use this method to start an application from a bookmark or a favorite.
SGD supports the RANDR X extension for multiple monitor displays. Using RANDR is the easiest way to configure SGD to work with multiple monitor displays.
To configure SGD to work with multiple monitors, perform the following configuration steps:
(Optional) Configure the maximum display size.
Configure the array to use RANDR.
Configure the application objects to use RANDR.
To avoid problems with clipped windows, you might want to increase the display resolution for the X Protocol Engine.
In the Administration Console, go to the Protocol Engines → X tab for each SGD server in the array and change the Client Window Size settings. In the Maximum Height and Maximum Width fields, type the highest display resolution you expect to support.
Increasing the Maximum Width and Maximum Height attributes increases the memory requirements for applications on both client devices and SGD servers.
Alternatively, use the following command:
$ tarantella config edit --array \ --xpe-cwm-maxwidthpixels
\ --xpe-cwm-maxheightpixels
The following example specifies a maximum display size of 3200 x 2048 pixels.
$ tarantella config edit --array \ --xpe-cwm-maxwidth 3200 \ --xpe-cwm-maxheight 2048
Repeat the configuration for each application that is displayed on multiple monitors.
By default, using the RANDR extension is disabled for the array.
Go to the Global Settings → Client Device tab in the Administration Console and select the RandR Extension check box.
You can also use the following command to to enable RANDR for the array:
tarantella config edit --array-xrandr-enabled 1
In the Administration Console, go to the Presentation tab for the application object and select the Window Size: RandR Extension check box.
You can also use the following command to enable RANDR for an application object:
$ tarantella object edit --name app-name
--xrandr 1
The easiest way to configure SGD to work with multiple monitor displays is to use the RANDR extension, as described in Section 4.8.2, “Using RANDR for Multiple Monitor Displays”.
In some situations you may not want to or may not be able to use RANDR. This topic describes an alternative configuration method that does not use RANDR.
You can use multihead or dual head monitors with
SGD. However, if any of your X applications are
configured with a Window Type (--displayusing
)
setting of Client Window Management or Kiosk, you might have to
change the application and monitor configuration to be able to
use multiple monitors.
See also Section 4.2.1, “Configuring X Application Objects”.
To configure multiple monitors to work with X applications that have a Window Type setting of Client Window Management or Kiosk, perform the following configuration steps:
Disable shared resources.
Configure the correct desktop size.
Set up the monitors.
SGD enables similar applications to share resources, to reduce memory overhead. This feature must be disabled for any applications that you want to display using multiple monitors.
In the Administration Console, go to the Performance tab for the application that is displayed on multiple monitors and deselect the Share Resources Between Similar Sessions check box.
Alternatively, use the following command:
$ tarantella object edit --name obj
--share false
Repeat the configuration for each application that is displayed on multiple monitors.
You must ensure that the SGD server sends the client device enough space to display all the monitors on the desktop.
This increases the amount of memory used on the client device and on the SGD server.
You must configure SGD so that it sends the size of the entire desktop area to the client device, and not just the size of the primary monitor. The size of the entire desktop area is shown by the “virtual screen” in the following diagram.
For example, if the dimensions of Monitor 1 in the diagram are 1200 x 768 and the dimension of Monitor 2 are 800 x 600, then the desktop size that needs to be configured is 2000 x 768.
In the Administration Console, go to the Protocol Engines → X tab for the SGD server. For Client Window Size, type the dimensions in pixels of the virtual screen in the Maximum Height and Maximum Width fields.
Alternatively, use the following command:
$ tarantella config edit --array \ --xpe-cwm-maxwidthpixels
--xpe-cwm-maxheightpixels
Repeat this configuration for each SGD server in the array.
X applications can be displayed in kiosk mode on a multihead or dual head monitor.
You configure kiosk mode display features with the
<KioskArea>
entry in the
<localsettings>
section of the client
profile, profile.xml
on the client
device. If the <localsettings>
section
is not present in the client profile, create a new section.
The <KioskArea>
entry defines the
screen area used by kiosk mode. The available values are as
follows:
virtual – Uses the virtual screen size. All monitors are used.
0 – Uses the primary monitor only. This is the default value.
1 – Uses the secondary monitor only.
n – (Multihead monitors only). Uses the nth secondary monitor only.
For example, to span the kiosk mode display across all monitors:
<KioskArea>virtual</KioskArea>
The desktop size for kiosk mode applications can also be configured from the webtop. Use the Span Multiple Monitors (Kiosk Mode) option in the Client Settings tab.
When using Windows Remote Desktop Services, the performance of Windows applications might be poor. This is caused by using animation effects and other presentation settings in the Windows session. Performance is affected because these features require more screen updates and can greatly increase the bandwidth used. The problem is more severe on slower connections.
The causes of these problems can include the following:
Animated mouse cursors
Mouse cursor shadows
Screensavers
Animated icons in the notification area
Animated images in programs
Animated wallpaper
Images used as wallpaper
Font smoothing
By default, the SGD Remote Desktop Client, ttatsc, enables all of these features except for font smoothing.
You can turn off presentation features by configuring one or more attributes for the Windows application object. The attributes you can configure are listed in the following table.
Attribute | Description |
---|---|
Cursor Settings | Disables mouse pointer schemes and customizations. |
Cursor Shadow | Disables the shadow on the mouse pointer. |
Desktop Wallpaper | Disables the desktop wallpaper. Disabling the wallpaper can reduce the amount of data that is updated when users move items around the desktop. |
Font Smoothing | Enables font smoothing for text in the application. |
Full Window Drag | Disables the option to show the contents of a window while it is moved. |
Menu Animations | Disables transition effects for menus and tooltips. |
Theming | Disables desktop themes. |
This section includes some tips on how to get the best user experience when using SGD with Java Desktop System.
You can improve performance of Java Desktop System desktop sessions and applications in the following ways:
Configure the X application object for Java Desktop System
Disable some default Java Desktop System settings
For a Java Desktop System desktop session or application,
ensure that you specify the correct command path for the X
application object. Set the Application Command
(--app
) attribute to
/usr/dt/config/Xsession.jds
. Using a path
of /usr/bin/gnome-session
results in some
Java Desktop System configuration parameters being lost and
gives a poorer user experience.
To improve the display of animated effects, you can configure performance settings for the X application object. See Section 4.9.11, “An Application's Animation Appears 'Jumpy'”.
The performance of Java Desktop System desktop sessions and applications can be affected by animation effects and other default desktop settings. Performance is affected because these features require more screen updates and can greatly increase the bandwidth used. The problem is more severe on slower connections.
Performance can often be improved by turning off, or modifying, some of the following Java Desktop System desktop features:
Anti-aliased fonts
Large fonts
Login screen, splash screen, About screen, and Logout screen
Animations
Desktop applets
Showing window contents when dragging
Desktop wallpaper
Themes
A document object can refer to any URL. This can be any document on the web, including Oracle Open Office documents, or Adobe™ Acrobat files. A document can also refer to a web application.
As it is the user's client device that actually fetches the URL, firewalls, or other security measures can prevent a user from accessing a document.
You can use SGD to access web applications. A web application is simply a web page, or any URL, that requires the user to supply a user name and password for access. To give users access to a web application, you create a document object that links to the URL of the web application.
Unlike passwords for application servers, SGD cannot cache the user names and passwords for accessing web applications. However, you can configure web authentication, so that users can access SGD from a web application without having to log in again. See Section 2.6.4, “Web Authentication” for details. Alternatively, you can authenticate SGD users to the web application.
When accessing web applications, use a secure (HTTPS) web server, so that all communication is encrypted using SSL before transmission.
This section describes how to configure application objects for use in a virtual classroom.
You can use SGD shadowing to create a virtual classroom, where the pupils in the classroom shadow an application being demonstrated by a teacher.
To be able to do this, you have to create a teacher's application object and a classroom application object.
The teacher must start their application first, then the pupils start their classroom application to shadow the teacher. The classroom can only shadow Windows applications or X applications.
Only one person can use the teacher's application at any one time. If more than one person starts the teacher's application, the classroom shadows the application that was started last. For this reason, only give the teacher's application to one user. If you have several teachers, create separate application objects for each of them.
For the best results, configure the classroom application object as follows:
The classroom application must have a Color Depth of at least 16-bit.
The display size of the classroom application must be at least the size of the teacher's application.
Use a Window Type setting of Independent Window. The user experience may be poor if the application has a Window Type of Seamless Window or Client Window Management.
Disable the Share Resources Between Similar Sessions attribute for the application object.
When the teacher starts their application, information is stored on the SGD server about which application can be shadowed by the classroom. This information is not copied to the other members of the array. This means that if the classroom application is started on a different SGD server to the teacher's application, the classroom application fails because the information about which application can be shadowed is not available.
You can use load balancing groups to guarantee that the teacher and classroom applications are started on the same SGD server. You must set the load balancing group for the application server and the SGD server. Otherwise, only use classroom shadowing in an SGD array containing a single SGD server.
See also Section 4.9.9, “Using Shadowing to Troubleshoot a User's Problem”.
In the Administration Console, create a new Windows application object or X application object.
Go to the Launch tab and type one of the following in the Login Script field:
unixclass.exp
– If the
application is an X application
winclass.exp
– If the
application is a Windows application
Click Save.
Configure any other settings you want for the teacher's application.
Click the Hosting Application Servers tab and select the application servers that can run the application.
On the Assigned User Profiles tab, assign the teacher's user profile to the application.
In the Administration Console, create a new X application object.
The classroom application is an X application, even if the teacher's application is a Windows application.
The General tab is displayed.
Go to the Launch tab and configure the application as follows:
In the Application Command field, type /opt/tarantella/bin/bin/ttashadow.
In the Arguments For Command field, type -readonly -silent -pointer $SHADOWDISPLAY.
For the Connection Method, select the telnet option.
Select this option even if telnet is disabled for the SGD server.
In the Login Script field, type
pupil.exp
.
In the Environment Variables field, configure the
MYCLASS
variable.
The format is
MYCLASS="name_of_teacher's_application
".
For example,
MYCLASS=".../_ens/o=applications/ou=Finance/cn=XClaim"
.
Click Save.
Go to the Presentation tab.
For Color Depth, select 16-bit - thousands of colors and click Save.
Configure any other settings you want for the classroom application.
Go to the Hosting Application Servers tab and select the application servers that can run the application.
The ttashadow
application is only
available on servers where SGD is installed.
Go to the Assigned User Profiles tab, assign the user profiles of all users in the class to the classroom application.
The configuration required for Common Desktop Environment (CDE) applications depends on whether you want to run a desktop session or an individual application.
For CDE desktop sessions configured with a Connection Method of
ssh
, problems can occur when a user tries to
exit from the CDE session. The CDE session might hang, making it
impossible to log out normally from the system. See
Section 4.8.8.3, “Using CDE and SSH”.
To avoid font problems when using CDE applications, it is best to use a font server as described in Section 4.2.4.1.2, “Using a Font Server”.
To run a CDE desktop session through SGD, create an X application object with the settings shown in the following table.
Attribute | Setting |
---|---|
Application Command |
The full path to the
On the command line, use --app
|
Keep Launch Connection Open | Select the Enabled check box. On the command line, use --keepopen true. |
Session Termination | Select Login Script Exit from the list. On the command line, use --endswhen loginscript. |
Window Type | Select Kiosk from the list. On the command line, use --displayusing kiosk. |
Window Size | Select the Scale to Fit Window check box. Use this setting only if users suspend and resume the application on displays of different sizes. On the command line, use --scalable true. |
To run a CDE application directly, rather than from the CDE Front Panel, create an X application object with the settings shown in the following table.
Attribute | Setting |
---|---|
Application Command | The full path to the application you want to run.
On the command line, use --app
|
Keep Launch Connection Open | Deselect the Enabled check box. On the command line, use --keepopen false. Note This is the default value for this attribute. |
Session Termination | Select No Visible Windows from the list. On the command line, use --endswhen nowindows. Note This is the default value for this attribute. |
Window Type | Select Client Window Management from the list. On the command line, use --displayusing clientwm. |
Window Manager | Type the following in the field:
On the command line, use --winmgr '/usr/dt/bin/dtwm -xrm "Dtwm*useFrontPanel: false" -xrm "Dtwm*ws0*backdrop*image: none"'. |
If you have problems running an individual CDE application, configure a CDE desktop session as shown in Section 4.8.8.1, “Configuring a CDE Desktop Session” and run the application from the CDE Front Panel.
For CDE desktop sessions configured with a Connection Method of ssh, problems can occur when a CDE desktop user tries to exit from the CDE session. The CDE session might hang, making a proper logout from the system impossible.
The CDE session displays a TT_ERR_NO_MATCH
error message.
The workaround for this issue is as follows:
Log in to the CDE host as superuser (root) and type the following commands:
# mkdir /etc/dt # mkdir /etc/dt/config # cp /usr/dt/config/sessionetc /etc/dt/config # cp /usr/dt/config/sessionexit /etc/dt/config # cp /usr/dt/config/sys.dtprofile /etc/dt/config # chgrp bin /etc/dt/config # chmod 555 /etc/dt/config/* # chown bin:bin /etc/dt/config/*
Add the following lines to the
/etc/dt/config/sessionetc
file:
if [ "$SSH_TTY" !="" ] then SSHPTTY=`echo $SSH_TTY | cut -c6-15` ps -ef | grep -v grep | grep $SSHPTTY | grep Xsession | awk '{print $3}' > /var/dt/tmp/$DTUSERSESSION/sshd_pid fi
Add the following lines to the
/etc/dt/config/sessionexit
file:
if [ -f /var/dt/tmp/$DTUSERSESSION/sshd_pid ] then /bin/kill -HUP ‘/bin/cat /var/dt/tmp/$DTUSERSESSION/sshd_pid‘ /bin/rm /var/dt/tmp/$DTUSERSESSION/sshd_pid fi
Add the following line to the
/etc/dt/config/sys.dtprofile
file:
dtstart_session[0]="/usr/local/bin/ssh-agent /usr/dt/bin/dtsession"
You can use SGD to access X applications and character applications on a VMS application server.
To configure SGD to access applications on a VMS server, you have to perform the following configuration steps:
Configure the login script used for the application.
Configure the transport variable in the login script.
Disable X security.
The login script used for the X application or character application must be configured.
In the Administration Console, go to the Applications →
Launch tab for the application object you want to configure.
In the Login Script box, type vms.exp
.
Alternatively, use the following command:
$ tarantella object edit --name obj
--login vms.exp
By default, the vms.exp
login script sets
the transport variable to TCPIP
. This
setting is correct for Digital TCP/IP stacks, including Ultrix
Communications Extensions (UCX).
If you need to change this variable, edit the transport variable setting in the login script. The transport variable is set by the following entry in the login script:
set transport "TCPIP"
Login scripts are located in the
/opt/tarantella/var/serverresources/expect
directory.
To use VMS X applications, you must disable X security in SGD. This is because SGD does not support X authorization for VMS X applications.
In the Administration Console, go to the Global Settings → Security tab and deselect the X Authorization for X Display check box.
Alternatively, use the following command:
$ tarantella config edit --security-xsecurity 0
SGD uses the third-party emulator application, TeemTalk for Unix, for 3270 and 5250 applications. See the TeemTalk for Unix User's Guides supplied with SGD for details.
The first time a user runs the 3270 or 5250 emulator, the
tta3270.nv
configuration file is created in
the user's home directory on the SGD server.