PCS 7 - V7.1 SP4 - Redundant Server to Client communication

Dear Friends,

I am having a problem in establishing a communication between a redundant server (Server 2) and clients.

There are redundant servers and 8 clients in the project. It was commissioned 2 weeks ago and everything was OK.

I deactivated the redundant server (Server 2) today for some reason and activated it again. Since then, the Server 2 is not communicating to the clients.

However, the Server is getting the data from the AS stations and all the S7 connections are healthy. But it is not communicating to the clients.

Now, all the clients are now communicating only on Server 1 and is showing that they are communicating to one server (Server 1) only. I am fearing the failure of Server 1 as well. Hence I need to make it redundant as early as possible.

Attached is the screenshot of the Status of client connections on Server 2 and WinCC diagnose folder.

The Terminal Bus Network is OK and I can access all the Client computers from Server2 and vice versa.

Here are few things I tried to get it right, but nothing was fruitful

1. I deactivated and started it again.

2. I restarted the PC and started the WinCC.

3. I deleted the previously downloaded project in the Server2, compiled the OS with "Generate Server Data" and downloaded the project again.

4. I changed the Terminal Bus port on the Server 2 to another LAN port and changed the selection of terminal bus in Simatic Shell.

5. Logged in as a different user and activated it.

6. Checked all the services in Windows (Windows server 2003 Standard) and compared with Server 1. Everything looked same.

7. Downloaded to one of the clients once again and checked.

8. Have restarted the windows ample no. of times.

Please let me know your feedback on how to resolve the issue.

Thanks,

Sudheendra