topic Re: passive ftp in Operating System - HP-UX

passive ftp

Barbara Kramer — Mon, 25 May 2009 12:19:44 GMT

Hi,
I need to ftp via vpn, therefore needing a passive ftp. I have written a script for normal ftp. I know ftp has a passive option, but one can only use it, once logged on to the server. I need a passive ftp, where I can log on, change dir at dest server an get and put files. I have checked out tftp, but I can not use user or change dir with tftp. Does anyone have any idea what HP has to offer for hpux 11.11?
thanks for helping
Barbara

Re: passive ftp

Dennis Handly — Mon, 25 May 2009 12:27:01 GMT

>but one can only use it, once logged on to the server.

What's wrong with that? Just issue the command after you have logged in.
What does your current script look like?

Re: passive ftp

Olivier Masse — Mon, 25 May 2009 12:27:37 GMT

Have you tried using "ftp -p" ?

Re: passive ftp

Barbara Kramer — Mon, 25 May 2009 12:37:04 GMT

Hi,
thanks for answering so quickly.
this is what my ftp scripts do today:

ftp -n -i -v 999.999.999.999 <

Re: passive ftp

mobidyc — Mon, 25 May 2009 12:43:27 GMT

Hi,

from the ftp man page :
-p Enables passive mode for data transfers.

you could also use the command "passive" to enable the passive connection once you are connected.

BR,
Cedrick Gaillard

Re: passive ftp

Barbara Kramer — Mon, 25 May 2009 12:48:37 GMT

Hi,
I have ajusted the ftp with the -p option. Evenso, I never heard one can use it like that, I have tried it, but unfortunately it gives error ftp: -p: unknown option
any other ideas?

Re: passive ftp

Barbara Kramer — Mon, 25 May 2009 13:01:28 GMT

Hi,
I know, there is a command -p or passive, once logged on to the server I need to go to. Yet, the other server only allows passive ftp login. I thought of tftp, but no change of directory or sign in with user is offered with tftp ;-((

Re: passive ftp

Dennis Handly — Mon, 25 May 2009 13:04:41 GMT

>unfortunately it gives error ftp: -p: unknown option

It's there on 11.23.

>But I can not even connect to the other server without passive ftp.

Hmm, I've been able to connect but quickly hang. Can you add "passive" before your first "cd"?

Re: passive ftp

Barbara Kramer — Mon, 25 May 2009 13:18:25 GMT

I am working on HPUX 11.11.
I have tried:
_________________________________
ftp -n -i -v 999.999.999.999 <

Re: passive ftp

Steven E. Protter — Mon, 25 May 2009 13:40:58 GMT

Shalom Barbara,

If you control both ends, consider openssh.

Password free it can make live much easier.

http://www.hpux.ws/?p=10

SEP

Re: passive ftp

Barbara Kramer — Mon, 25 May 2009 13:45:55 GMT

sep, thanks for answering,
I already tried to talk to the client, to use opensh. His firewall team only allows passive ftp. That is the only thing I can use. Maybe, I should install wget or pure-ftp?
Any experience with those?

Re: passive ftp

Steven Schweda — Mon, 25 May 2009 14:48:56 GMT

> [...] but one can only use it, once logged
> on to the server.

Unlike the "cd" and "mget" commands? What's
so hard about putting a "passive" command
where you need it?

> ftp: connect: Connection timed out

That's a "passive"-related problem?

Can you do a working FTP session
interactively? Might it make some sense to
try to get the basic procedure to work before
trying to create a script to automate that
procedure?

> Maybe, I should install wget or pure-ftp?

Wget can do FTP fetches. Its help ("-h")
suggests that it defaults to passive-mode
FTP:

[...]
FTP options:
[...]
--no-passive-ftp disable the "passive" transfer mode.
[...]

Re: passive ftp

Steven Schweda — Tue, 26 May 2009 03:34:47 GMT

> But I can not even connect to the other
> server without passive ftp.

This sounds wrong to me. Passive mode should
affect data-channel transfers, like directory
listings (dir/ls (LIST/NLST)) or file get/put
(RETR/STOR) operations. Other operations,
like user (USER, PASS), cd (CWD), and so on
should be done over the control channel, so
passive mode (or not) should not matter.

For a good time, try using "ftp -d" (or the
"debug" command) to let you see the message
traffic between your FTP client program and
the FTP server. To start, use your own FTP
server, so you have control over both ends.

Get connected, and do some work. I claim
that in non-passive mode, data-channel
transfers will involve PORT commands, and the
primary difference in passive mode will be
the replacement of those PORT commands with
PASV commands. And these will not be seen
during the login sequence, or cd actions, or
any other control-channel activity.

Now, if the troublesome FTP server is using
some non-standard port, or something like
that, then you might have some trouble
getting connected, but, as I understand FTP
(which is always open to some doubt), passive
mode (or not) should not affect the
connection+login sequence. If some odd-ball
port must be used, then I'd expect that to
affect both modes equally.