On a server that is running Windows Server 2003, the FTP service is
installed in Internet Information Services (IIS) 6.0.
The FTP clients establish passive mode connections to the FTP server.
Some
client connections never time out
even
when no data transfers
are in progress.
When this problem
occurs to
an FTP server that is under a
high
load
condition, new
client connections may be refused or existing client connections and data
transfers may be dropped.
Notes- Connection time-outs improve
server performance by reducing the
number
of processing resources that
are consumed by idle connections. For more information
about how to set connection time-outs,
refer to the "More information" section.
- When FTP clients connect to FTP servers to
transfer
data, the following passive
mode connection channels are established:
- Control channel: This channel is used to send requests and to receive replies.
- Data channel: This channel is used to transfer
file data.
- This
issue occurs in
a passive mode connection. Specifically,
this issue occurs when an FTP command that starts the data transfer is received
on the control
channel before the data connection channel is established.
Hotfix information
A
supported hotfix is available from Microsoft. However, this hotfix is intended
to correct only the problem that is described in this article. Apply this
hotfix only to systems that are experiencing the problem described in this
article. This hotfix might receive additional testing. Therefore, if you are
not severely affected by this problem, we recommend that you wait for the next
software update that contains this hotfix.
If the hotfix is available
for download, there is a "Hotfix download available" section at the top of this
Knowledge Base article. If this section does not appear, contact Microsoft
Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required,
you might have to create a separate service request. The usual support costs
will apply to additional support questions and issues that do not qualify for
this specific hotfix. For a complete list of Microsoft Customer Service and
Support telephone numbers or to create a separate service request, visit the
following Microsoft Web site:
Note The "Hotfix download available" form displays the languages for
which the hotfix is available. If you do not see your language, it is because a
hotfix is not available for that language.
Prerequisites
You must have the
FTP service
installed in IIS 6.0 to apply this hotfix. Additionally, the computer must be
running Windows Server 2003 Service Pack 1 (SP1) or Windows
Server 2003 Service Pack 2 (SP2).
Restart requirement
You must restart the computer if
any affected
files are
being used
when you apply this hotfix. To avoid having to restart the computer, stop
the FTP Publishing Service service
before you apply this hotfix.
Hotfix replacement information
This hotfix does not replace any other hotfixes.
File information
The English version of this hotfix has the file
attributes (or later file attributes) that are listed in the following table.
The dates and times for these files are listed in Coordinated Universal Time
(UTC). When you view the file information, it is converted to local time. To
find the difference between UTC and local time, use the
Time
Zone tab in the
Date and Time item in Control
Panel.
For all supported x86-based versions of Windows Server 2003 SP1
Collapse this tableExpand this table
| File name | File version | File
size | Date | Time | Platform |
|---|
| Ftpsvc2.dll | 6.0.3790.3015 | 127,488 | 27-Sep-2007 | 07:21 | x86 |
For all supported x86-based versions of Windows Server 2003 SP2
Collapse this tableExpand this table
| File name | File version | File
size | Date | Time | Platform |
|---|
| Ftpsvc2.dll | 6.0.3790.4159 | 127,488 | 27-Sep-2007 | 07:29 | x86 |
For all supported x64-based versions of Windows Server 2003 SP1
Collapse this tableExpand this table
| File name | File version | File
size | Date | Time | Platform |
|---|
| Ftpsvc2.dll | 6.0.3790.3015 | 177,664 | 27-Sep-2007 | 05:12 | x64 |
For all supported x64-based versions of Windows Server 2003 SP2
Collapse this tableExpand this table
| File name | File version | File
size | Date | Time | Platform |
|---|
| Ftpsvc2.dll | 6.0.3790.4159 | 177,664 | 27-Sep-2007 | 05:56 | x64 |
For all supported IA-64-based versions of Windows Server 2003 SP1
Collapse this tableExpand this table
| File name | File version | File
size | Date | Time | Platform |
|---|
| Ftpsvc2.dll | 6.0.3790.3015 | 338,432 | 27-Sep-2007 | 05:11 | IA-64 |
For all supported IA-64-based versions of Windows Server 2003 SP2
Collapse this tableExpand this table
| File name | File version | File
size | Date | Time | Platform |
|---|
| Ftpsvc2.dll | 6.0.3790.4159 | 338,432 | 27-Sep-2007 | 05:44 | IA-64 |
To work around this problem, use
one of the following methods.
Method
1Stop
and then start the FTP site in IIS Manager.
Method 2Open
IIS Manager. Locate the FTP site, and then open the FTP site
properties dialog box. Click the
Current Sessions...button
to open the
FTP User Sessions
dialog box,
and then manually disconnect the client connections.
Note These workarounds may disconnect active connections while
they are transferring
data.
We recommend that you apply the hotfix to resolve this problem.
Microsoft
has confirmed that this is a problem in the Microsoft products that are listed
in the "Applies to" section.
For more information about how to configure FTP site
properties in IIS 6.0, visit the following Microsoft Web site:
For more information about how to set connection time-outs in IIS
6.0, visit the following Microsoft Web site:
For more information about server-to-server FTP transfers,
visit the following Microsoft Web site: