Thanks for this clue.
On client side, I see no explicit errors, except:
tail -f /var/log/apache2/error.log
[Mon Nov 12 15:58:57 2007] [error] an unknown filter was not added: PHP
That is described in this forum as not really problematic (resulting of "SetOutputFilter PHP" and "SetInputFilter PHP" in /etc/apache2/vhosts/Vhosts_ispconfig.conf)
On the server side:
- First 200 is remoting connection OK, then Client add gives a 500 error...
tail -f /root/ispconfig/httpd/logs/access_log
18.104.22.168 - - [12/Nov/2007:16:09:53 +0100] "POST /remote/index.php HTTP/1.0" 200 2039
22.214.171.124 - - [12/Nov/2007:16:09:53 +0100] "POST /remote/index.php HTTP/1.0" 500 0
But Client is created! My client script is fine as it works nicely on my first server...
How could I debug more?