We use an automated telnet session to obtain sensor data from the CMC. The application executes periodically (every 10 minutes), connects to the server, send the login and password (the server is current in a closed test environment and thus security is not an issue), sends the getsensorinfo command, obtains the results, sends an exit command (to gracefully shutdown the telnet session) and then disconnects.The application then trips an audible alarm on the remote computer if the sensor data indicates that the server temperature has exceeded a pre-set temperature.

When the application is scheduled periodically, it is able to connect to the CMC and get the desired data for a while but eventually the CMC stops processing telnet connections. It still allows telnet connection to be made to the CMC and allows the login and password to be entered but it never initiates the telnet prompt for any further telnet commands (i.e. the session hangs after entry of the password). This was confirmed by starting a telnet session manually and seeing that the session hangs after the password prompt.

I have not done an analysis on how many times the application is able to obtain the sensor data successfully before the CMC starts to reject it but it is less than 16 hours worth of connections (i.e. when I schedule the periodic running of the application before I leave work, it has stopped being able to connect by the time I return the next day).

Disconnecting the CMC to cause a failover, reset the problem but the problem eventually returns.

Does anyone know why this is happening and/or what can be done to avoid/mitigate it?