On Monday, 01/12/2009 at 12:01 EST, Hans Rempel <[email protected]> 
wrote:
> I?m having problems getting Filezilla from displaying the directory of 
my files 
> on the screen. I reviewed the list for past posts and have changed my 
> LISTFormat to UNIX without success. 
>
> Filezilla does make a SSL connect to my system but the directory display 
is 
> failing at this point.

This is often due to Encryption Meets Firewall.  Deep-inspection firewalls 
watch the FTP control connection and only open the needed ports based on 
seeing the port numbers on the PORT and PASV commands.  (A DIR opens a 
data connection just like GET or PUT.)  With the control connection 
encrypted, the firwall can't read the control connection.  And it doesn't 
matter whether you are operating in passive or active mode.

With z/VM 5.4 you can use the FTP CCC (Clear Command Channel) subcommand 
to return to plain-text after entering your user ID and password.  Then 
the fw can see the PORT and PASV commands, but the data transfer will be 
encrypted.

If you don't like that (or are using earlier release of z/VM, or 
workstation ftp client doesn't support it), then you have to drill holes 
in the firewall.
(a) Use passive FTP, 
(b) Code PassivePortRange in SRVRFTP CONFIG,
(c) RESERVE those ports for your FTP server in PROFILE TCPIP
(c) open the port range specified in (b) in the firewall.

Alan Altmark
z/VM Development
IBM Endicott

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