Article ID: 2700248 - View products that this article applies to.
A server that is running Microsoft Forefront Threat Management Gateway (TMG) 2010 may stop accepting all new connections and may become unresponsive. This issue may occur after several hours to several days of server up-time.
When this condition occurs, users may be unable to establish a Terminal Services session to the server. User authentication of requests may also be unsuccessful, because the Forefront TMG server may lose its connection to the domain controller.
In this case, the performance monitor may display the following:
This problem may occur because of a race condition between the Forefront Threat Management Gateway Firewall service and local system processes such as the DNS Client service or the Local Security Authority Process (LSASS). Specifically, in a heavy load environment, when all work items that have to be completed are processed, insufficient priority is given to some tasks that should be completed first. This causes the race condition.
To resolve this problem, install the hotfix package that is described in the following Microsoft Knowledge Base article:
(http://support.microsoft.com/kb/2735208/ )Rollup 3 for Forefront Threat Management Gateway (TMG) 2010 Service Pack 2
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
This fix prevents the race condition between the Forefront Threat Management Gateway Firewall service and local services that are running on the Forefront TMG server by reserving more worker threads and giving increased priority to more important tasks that are related to local host traffic processing.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/824684/ )Description of the standard terminology that is used to describe Microsoft software updates
Article ID: 2700248 - Last Review: January 10, 2013 - Revision: 2.0