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FTP client

Hi!
I'm currently trying to retrieve a file from another machine on my network
using Internet Toolkit and FTP.
I am able to connect and logon and cwd on the remote system but when I try
to retrieve a file using either low or mid or hi level vi's
I get the message "Can not open connection to xxx.xxx.xxx.xxx.
My machine has got two network cards or actually two "ports" on one card.
The IP-addresses for these cards are completely different.
In the error message I get the IP address of the first "port" while I am
using the second "port" for my FTP.
I tried to swap "ports" and everything worked.
I'm running my vi's on a NT4.0 machine with plenty of everything!

/Roger
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Roger Jonsson wrote:

> I'm currently trying to retrieve a file from another machine on my network
> using Internet Toolkit and FTP.
> I am able to connect and logon and cwd on the remote system but when I try
> to retrieve a file using either low or mid or hi level vi's
> I get the message "Can not open connection to xxx.xxx.xxx.xxx.
> My machine has got two network cards or actually two "ports" on one card.
> The IP-addresses for these cards are completely different.
> In the error message I get the IP address of the first "port" while I am
> using the second "port" for my FTP.

It sounds as if something might be going wrong under the hood of the FTP VIs,
but it could also be related to the network configuration you've got. I'm
going to speculate that the error occurs
when the FTP client tries to
establish the duplex connection (open up a second connection on a different
port) required to transfer files. This might explain why the initial
username/password step works OK, but you get an error later in the transfer
process.

I'm not aware of how the second connection is created, and which side
initiates it, but I do have one question for you: do you have two distinct DNS
names that map to your two distinct IP addresses? If you've got the two
addresses, but you have only configured a network name for one of them, and if
the second FTP connection is established by doing a DNS lookup on the machine
name, then that could perhaps explain the error.

I'll ask around to see if anyone else has any ideas.

Regards,
John Lum
National Instruments
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Thank you for your answer Mr. Lum.
I have tried to FTP from two different non Windows systems (VMS and MTOS)
with the same result.
I have not tried to FTP to a NT system because I don't have one with a FTP
server.
The test I did just a minute ago was to enable Search Order for DNS
but I can not specify two different DNS names for the different "ports", I
suppose that it has to do with that these "ports" are physically on the same
network adaptor?.
I also enabled Wins and put the right address into the Primary Wins server
with no luck at all!
The test was done step by step (lots of restarting!!).
I'm not really good at DNS or network setup so if you know something more
about this please send me a message!

Thanks /Roger

John Lum wrote in message <388E141B.CBF7BB43@alum.mit.edu>...
>Roger Jonsson wrote:
>
>> I'm currently trying to retrieve a file from another machine on my
network
>> using Internet Toolkit and FTP.
>> I am able to connect and logon and cwd on the remote system but when I
try
>> to retrieve a file using either low or mid or hi level vi's
>> I get the message "Can not open connection to xxx.xxx.xxx.xxx.
>> My machine has got two network cards or actually two "ports" on one card.
>> The IP-addresses for these cards are completely different.
>> In the error message I get the IP address of the first "port" while I am
>> using the second "port" for my FTP.
>
>It sounds as if something might be going wrong under the hood of the FTP
VIs,
>but it could also be related to the network configuration you've got. I'm
>going to speculate that the error occurs when the FTP client tries to
>establish the duplex connection (open up a second connection on a different
>port) required to transfer files. This might explain why the initial
>username/password step works OK, but you get an error later in the transfer
>process.
>
>I'm not aware of how the second connection is created, and which side
>initiates it, but I do have one question for you: do you have two distinct
DNS
>names that map to your two distinct IP addresses? If you've got the two
>addresses, but you have only configured a network name for one of them, and
if
>the second FTP connection is established by doing a DNS lookup on the
machine
>name, then that could perhaps explain the error.
>
>I'll ask around to see if anyone else has any ideas.
>
>Regards,
>John Lum
>National Instruments
>
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Message 3 of 5
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i want to know how to send a file using ftp?
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Hello,

Using FTP is a great way to transfer files. We have included several examples of how to do this as shipping examples with LabVIEW. You can access these examples by going to Help -> Find Examples and then searching with the keyword FTP. Two examples of transferring files will appear. Also I am attaching a vi to the bottom of this post that demonstrates how to use datasocket and ftp to transfer files. By editing these vis to meet your needs you can easily transfer files using FTP.

Thanks,
Caroline
National Instruments
Thanks,
Caroline Tipton
Data Management Product Manager
National Instruments
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