Hi, I didn´t make any special configuration to make this work.
I´ve tried with QoS on defaut class, on and off, without any changes in both cases.
The connection is made through port 21, using PASV (passive), Wan is a direct connection with fixed IP, net balancer is set to direct clients directly to this connection, without load balancing.
The other applications work normally, even FTP clients when listing folders or downloading. Just on uploads the connection starts with full speed (link speed) and immediatelly starts to fall until reaches 0kbs. Then I receive an error from FTP client and I have to reconnect to FTP server.
The only rule added to Firewall is:
ACCEPT all opt — in ETH00 out ETH01 0.0.0.0/0 -> 0.0.0.0/0
(In chain Forward – using ZS interface).
Hope this helps to clarify. Thanks!