Wednesday, December 28, 2011

Using Session Linger in XenApp 6.5

As a Citrix administrator, did you come across the the case like below ?

A user told you that she cannot launch a published application e.g. Microsoft Word. When she try to click on icon on Web interface, no response. During investigation, you found that she just close a published application and try to launch another.

For user, it is a very common operation. However, it may be a trouble in XenApp environment.

The sense behind:

When user try to close published application (i.e. click “X” at the top right corner of windows box), ICA session ended and user logoff XenApp server. When user try to launch published application, the problem appear if this application is installed on same XenApp server as the previous session is ending and Windows logoff in progress.

The common solution is to disable Session Sharing feature of XenApp. However, this cause other problem that multiple sessions from same user even connecting to same XenApp server. It is not a good idea.

In XenApp 6.5, new solution comes in --- Session Linger

Session Linger is a new feature in XenApp 6.5 that allows user ICA session to hold as active state for a period of time after the last published application close.

Let 's see how to configure it.
Session Linger is configured in XenApp user policy. The following is an example:

Linger Disconnected Timer interval --- time to change the session to disconnected state after linger activated. (it is useless if its value is greater than Linger Terminate Timer Interval.) 
Notes: XenApp will kill disconnected session according to ICA connection configuration
Linger Terminate Timer Interval --- length of time that session lingering will activate. The ICA session will end after this time period.

When Session Linger function, the session state will appear as "Lingering" like the following screen

During "Lingering" state, the session is still active so that user can still launch another published application in this XenApp server in same session (remember "Session Sharing"?)  without problem.

After "Session Disconnected Timer Interval" expires, you will the "Disconnected" state like the screen below

 User can still reconnect this disconnected "Lingering" session.

How long do you need to set this Linger Terminate Timer ? It depends on users behavior in your environment. 15 min is a common value in customers.

Any comment ?

1 comment: