alan tv§mجrë,Š‰ìš+¢ÊµÊ&

I've setup a IIS6 server both WEB & FTP services run normally. However, it
seems don't support MDTM command when using FTP client (e.g. ws_ftp &
dreamweaver) to update file. (i.e. the timestamp of the file updated cannot
be preserved).

I can't find any do***ent talking about from Microsoft.
Any idea?

Thanks in advance.

bernard

Have you tested it ?
use ftp.exe command line tool to test.

ftp> quote mdtm aaa.log
213 20040524080232

afaik - IIS5/6 both support mdtm.

--
Regards,
Bernard Cheah
http://www.tryiis.com/
http://support.microsoft.com/
http://www.msmvps.com/bernard/

alan tv§mجrë,Š‰ìš+¢ÊµÊ&

Bernard,

Thanks for your reply!
Yes, I've tested with ftp.exe command prompt before. However, it just can
update the time when the file was being uploadad to FTP.

For example,
The original timestamp is 18:21 19 May 2004 (20040519182120), when the file
is being uploaded to FTP, the timestamp will then change to 20041117153020.
(current uploaded time).

Extracted log from WS_FTP:
WS_FTP>STOR a.xls


In additional, if the file is being uploaded to FTP, I can use ftp.exe
command line of MDTM command like:
FTP>quote mdtm a.xls
213 20041117153020

However, the timestamp is not preserved.

Alan

alun jones [msft]

The MDTM command, as specified in
http://www.ietf.org/internet-drafts/draft-ietf-ftpext-mlst-16.txt, does not
allow for changing the modification time of a file. Your client program is
trying a non-standard extension to a command that hasn't even been made into
an RFC yet.

The chief reason the MDTM command hasn't been extended in this manner by the
FTPEXT working group is that the command you are trying could not be
uniquely distinguished as being a request to change the modification time,
since there could be a file named "20040619182120 a.xls", that you could be
asking for the time on. Worse, in the other direction, if there was a file
named "19960517180300 DigiPic.jpg", and you asked for the modification time
of that file, you'd get back an unpredictable response. It would be a very
bad thing to design or implement a command that could cause (even rarely)
essentially random behaviour to happen.

Alun.
~~~~

alan tv§mجrë,Š‰ìš+¢ÊµÊ&

Alun,

Do you mean although IIS 5/6 support this command, it still doesn't allow
user to modify the timestamp of the file as this action hasn't been allowed
to made into RFC. Does IIS just support command in RFC (how about other
draft?) Can I find any do***entation in Microsoft talking about any RFC
supported in IIS 5/6?

Actually, the reason why I post this message is one user incident:
He tried to use "synchronization feature" in dreamweaver to compare &
synchronize the file in FTP server & his PC. However, it seems not stable
when using this feature (Sometime it can detect the different timestamp of
the file but sometime can't). So I just suggest him don't rely on this
feature on my FTP server. Am I correct?

Since I know that other FTP servers support this feature (e.g. Serv-U FTP),
user may claim my FTP server is not user-friendly.

Alan

bernard

Let's Microsoft people address your issue...

I see Alun is taking care of this thread.

--
Regards,
Bernard Cheah
http://www.tryiis.com/
http://support.microsoft.com/
http://www.msmvps.com/bernard/

alun jones [msft]

To clarify:

The MDTM command is in an Internet-Draft, and has not yet made it into RFC
form.

The operation you are looking for, to set the modification time by the MDTM
command, is not do***ented in an Internet-Draft _or_ an RFC, because it is
potentially unpredictable. You are asking for a feature that is completely
undo***ented, and known to be unreliable even when implemented as you describe.

That may be an issue with his client software - the FTP server in IIS does
not support changing the modification time of files. There are a number of
other ways to achieve this, but not through FTP. One way, for example,
would be to upload a .ZIP file through FTP, and have someone local to the
site unzip the file, preserving the modification time.


Users may just as correctly claim that Serv-U's support of MDTM to change
the modification time could lead to some inconsistencies between behaviour
and intent. Different FTP server authors will make different choices as to
which operations are justifiable, and which cause sufficient concern that
they should not be implemented. Note, for instance, that the Internet-draft
describing MDTM's behaviour was written by the author of an FTP server, and
was reviewed, discussed, edited and approved by the IETF FTP Extensions
Working Group, which consists of authors of FTP implementations - server and
client. Discussion on that group included discussion of this feature, and
it was decided that, since the feature contained possibilities for
inconsistent and unpredictable behaviour, it was not worth do***enting in
the Internet-Draft.

There has been discussion among the FTPEXT WG members as to how best to
provide a feature to set attributes of a file, including the modification
time, and there will possibly be a further Internet-Draft (that will
eventually become an RFC) to describe how this can be done. Until then,
there is no do***ented standard way to alter the modification time of a file
through FTP.

You can even look on this as a security feature, in that you are able to
tell at what time the file was really uploaded through FTP, rather than what
time the user wanted you to think it was uploaded. This feature is also
used by FTP mirroring software to ensure that files are correctly updated
only when necessary.

Alun.
~~~~

alan tv§mجrë,Š‰ìš+¢ÊµÊ&

Alun,

Oic, now I know the reason why IIS don't support this feature.

Last question, where can I find do***ent talking about what RFC followed in
IIS?

Thanks for your help! Also thanks Bernard.

Bests,
Alan

bernard

This kb has the RFC detail -
Information About the IIS File Transmission Protocol (FTP) Service
http://support.microsoft.com/?id=283679

--
Regards,
Bernard Cheah
http://www.tryiis.com/
http://support.microsoft.com/
http://www.msmvps.com/bernard/

modification

file


what


updated

alan tv§mجrë,Š‰ìš+¢ÊµÊ&

Thanks Bernard.

Alan