I upgrade the server from build 10181 to build 10574, and the server was successfully upgraded.
However, some of my build agents failed to upgrade and become disconnected (MSG: Ping failed, check firewall on agent machine).
I checked the server log file and those failed build agents all point to the same IP address (http://188.8.131.52:9090) which I have no idea where this IP addres is from.
I tried to re-install build agent manually and rename build agent but the server is not able to find this buld agent anymore.
How do I make these build agents beeing connected to the server again? By changing IP address back? But how?
Please HELP -- we have large projects to run and currently we are short of 'succeeded' agents..