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iis ftp : FTP transmission issue


noone
5/30/2006 12:21:53 PM
The problem is that the FTP going out from the server will work for a
certain time then will fail pushing files.

Here is how it happens:

From the DOS prompt of the server

ftp (IPaddress)

UserName ftp_user

Password *****

cd Folder

cd Folder

bin

put a.ttt

You can do the put a few times and eventually after 4 or 5 attempts it will
fail.

On a second site it does the same...

Sometimes it will work for hours and when it blocks it takes many attempts
to let a few files across then blocks again.

I can easily loose an hour just waiting at the process to be completed.

I'm running a Brand new box Dell PowerEdge 1850, dual processors, 4 Gb ram
and 140 GB Hdd, with Windows Server 2003 R2 SP1 and IIS 6.0. The local
Windows firewall is not enabled and the box is sitting behind a corporate
firewall. Port 21 is enabled OUT for everyone on the firewall, with no
restriction.

The FTP "IS" working, but it is maddeningly unreliable. These files are
critical for one of our departments. This process is set in stone (Hard
coded ) by the vendor and they are saying that there is an issue on my end,
but for the life of me, I can't find out what "IT" is.

Jimmy Chu
5/30/2006 2:12:02 PM
This sounds just like what I'm encountering...


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noone
5/30/2006 3:43:17 PM
If this is a Firewall issue, then why are there any file transfers allowed
at all. If the Firewall is not configured to allow access on the undefined
port, then it should deny access entirely, not after a half dozen files get
transfered... ????

Firewalls are just that... walls. They stop access in, or out, defined by
the user. Is there some magic I'm missing here...?

:-)



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Robin Walker [MVP]
5/30/2006 5:57:05 PM
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Please clarify this: you are using the ftp *client* program on your IIS
server?
So this query has nothing to do with IIS?

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What is it that you are connecting *to* here? Someone else's remote FTP
server, or what?

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What do you mean by "second site"?
Do you mean:
(a) the same ftp client connecting to a different remote server?
(b) an ftp client at a different site connecting to the same remote server?

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What is the relevance of this information if you are not using this IIS, but
just using an ftp client program?

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If you are using the ftp line-mode client built into Windows, then it will
be functioning in Active (PORT) mode. Only the command stream uses port 21
on the remote server. The data transfers will be made on a connection
*from* the remote server *to* your ftp client: that is, an incoming
connection through your firewall, even though you are PUTting data from the
client to the remote server, the TCP connection on which this happens was
made the other way around. Your firewall might not be happy with this, or
might be timing these connections out.

I suggest that it is all a firewall problem.

You might care to do some experiments with alternative third-party ftp
clients that can use passive mode FTP, to see whether they work better.
That assumes that your firewall will let the passive mode connections out.

--
Robin Walker [MVP Networking]
rdhw@cam.ac.uk

Robin Walker [MVP]
5/30/2006 11:03:06 PM
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A time-out, maybe?

Do the experiment - try the connections without an intermediate firewall.

--
Robin Walker [MVP Networking]
rdhw@cam.ac.uk

Bernard Cheah [MVP]
5/31/2006 12:00:00 AM
If you are referring uploading the same file (same filename) within a short
period, then I'm guessing you hitting this issue.
Access Is Denied When Attempting to Put Files on FTP Server
http://support.microsoft.com/?id=182626

Lot of 'weird' stuff in IIS ftp, so try disable the memory caching and see
how it goes.

--
Regards,
Bernard Cheah
http://www.iis.net/
http://www.iis-resources.com/
http://msmvps.com/blogs/bernard/


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noone
6/5/2006 12:17:11 PM
Turns out that the FTP client at the command prompt is stuck in Active mode.
You can type Litteral PASV, or Quote PASV all day long, but it will never
actually switch to passive mode. Therefore, you will need to open up port
20 incoming and outgoing, then define and enable a range ports for the FTP
connection. ( hundreds of ports) Very Unsecure...

To cut this all short, Command prompt FTP is BAD news... Use a secure FTP
client (SSH, or some other form of encrption / secure connection) that
allows you to use Passive mode FTP. Either that or Drop your FTP server in
a DMZ, segregate it and isolate it. Then hope it doesn't blow up in your
face. Remeber that depending on what you are hosting on this FTP site, you
may need to enable traffic to and or from this server onto your network. (So
much for security.) If you already have a DMZ, you could further endanger
these other clients, depending on your IP addressing and routing policy on
the DMZ....

Very Uncool, but considering FTP.exe it was orriginally developed in 1971, I
guess I can't blame the people who developed it... Just the programmer who
hard coded it into my new software...

;-)

Thanks for all the help.



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Bernard Cheah [MVP]
6/6/2006 12:00:00 AM
ftp.exe is an active mode client. you can query passive mode via it, but not
act as a passive mode client.
and it is very basic and most of time for troubleshooting usage + minor non
production usage online.

--
Regards,
Bernard Cheah
http://www.iis.net/
http://www.iis-resources.com/
http://msmvps.com/blogs/bernard/


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engfelt NO[at]SPAM gmail.com
6/12/2006 1:19:46 PM
Try psftp.exe (console), flashfxp (gui and console) or smartftp (gui).
These clients can handle sftp and ftps as well. (ssh or ssl/tls)

If you have access to the IIS-ftp-server then these might help as well:
Forward Port 20-21 and the passive mode ports:
For Windows 2003 Server

a) To Enable Direct Metabase Edit
1. Open the IIS Microsoft Management Console (MMC).
2. Right-click on the Local Computer node.
3. Select Properties.
4. Make sure the Enable Direct Metabase Edit checkbox is checked.

b) Configure PassivePortRange via ADSUTIL script
1. Click Start, click Run, type cmd, and then click OK.
2. Type cd Inetpub\AdminScripts and then press ENTER.
3. Type the following command from a command prompt.
adsutil.vbs set /MSFTPSVC/PassivePortRange "5500-5700"
4. Restart the FTP service.

http://support.microsoft.com/kb/555022/en-us

Best regards
Niklas Engfelt



Bernard Cheah [MVP] skrev:

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