I've connected over ssh2 using ssh2_connect to a server, but I don't see any method in the manpages for how I should end the connection.
I'm not exactly a fan of waiting for a script to end before I disconnect.
Can I use fclose? That doesn't sound right...
Just unset($connection) your connection variable or ssh2_exec($connection, 'exit'); might do it.
You could probably do the following in order to be even more convincing!
ssh2_exec($connection, 'exit');
unset($connection);
If you were using phpseclib, a pure PHP SSH implementation, you could do $ssh->disconnect(). phpseclib's destructor calls it but you could call it manually as well.
Flask
ssh2_exec('logout') should kill your session…
来源：https://stackoverflow.com/questions/5820089/disconnect-from-ssh2-connect