If an OPC Client crashes unexpectedly, it will take the OPC Server 6 minutes to determine that it is necessary to clean up the connections. Microsoft COM and DCOM will wait six minutes prior to timing out and informing the OPC Server that the connection is down. This can result in an increase in the number of client connections if the client repeatedly connects and disconnects.One way to alleviate this issue is to install MatrikonOPC Tunneller between machines. The Tunneller components communicate via TCP/IP, and the timeouts can be manually configured to suit your needs. Tunneller can also be used to ensure secure communication across firewalls.
Click here for more information or to download MatrikonOPC Tunneller.
Click here for video tutorials demonstrating the installation and configuration of MatrikonOPC Tunneller.