Best strategy to detect that the connection is down?

[cliviu]

Hi,

it looks like the method SSHClient.isConnected() will not detect that the server is down after an initial connection is established and afterward the server is shut down.

I have tried even to call SftpClient.ls("/") and surprisingly I get an answer even if the server is not running.

I have also set the timeout to a lower value but still no improvement 
sftpClient.getSFTPEngine().setTimeoutMs(3000);

What is the best approach to recognize when the connection is down?

Thank you!