Directory and Resource Administrator 6.x
Assistant Admins attempting to launch the DRA MMC interface using a Citrix or Terminal services session are unable to establish new connections.
Client ports on a Citrix or Terminal server machine do not close and remain in the 'established' status even after users disconnect their sessions.
Directory and Resource Administrator (DRA) uses Distributed Component Object Model (DCOM) calls. If DCOM calls are made between two COM+ server applications on two different computers under heavy load, the COM+ applications may consume all available client ports between 1024 and 5000 and cause high CPU utilization. Performing a NetStat (NetStat /? at the command prompt) on the machine displays several thousand connections as established even though very few users may be connected to this particular server at this time. Microsoft has confirmed this to be a problem with Microsoft COM+ version 1.0 where client ports are not freed after the session has been disconnected.
This issue is resolved by installing Windows 2000 SP2 on the Citrix server running the DRA MMC. For more details, please review the following Microsoft Knowledge Base article:
Q290512 FIX: COM+ Applications Consume All Available Client Ports Between 1024 and 5000 and Cause High CPU Utilization.
As a workaround, restarting the COM+ server application will free up the client ports but the problem will reoccur over a period of time.