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inetserver asp general : IIS won't recognize if an ASP page has been changed



Aaron Bertrand [MVP]
11/16/2003 10:42:38 AM
Usually to prevent a *browser* from caching pages locally or on a proxy, you
*must* send cache-busting headers to the client.

However, depending on IIS settings, it has also been known to keep around
"sticky" old versions of a page in its cache (this is not specific to IIS 6
and is not directly related to the location of the virtual directory).
Sometimes you have to "kick" IIS to make it release its cache.

To see both techniques see http://www.aspfaq.com/2022


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Evertjan.
11/16/2003 1:33:44 PM
Michael G. Schneider wrote on 16 nov 2003 in
microsoft.public.inetserver.asp.general:

[quoted text, click to view]

Tap your favored tune on the F5 key.

More serious,

[quoted text, click to view]

Yes, this is normal behavour.

[quoted text, click to view]

Shorten the expiring time of the page, perhaps even to zero:

<% Response.Expires = 0 %>

How else could the new browser[window] know that the cached page is not
reflecting the newest content anymore?

--
Evertjan.
The Netherlands.
Michael G. Schneider
11/16/2003 2:17:00 PM
With Windows 2003 Server...

Imagine the following scenario: there is a simple ASP page, for example just
a single Response.Write statement. There is a virtual directory pointing to
the directory, where the ASP page is stored.

If I change this ASP page and hit the refresh button on the client browser.
I can then see the following behaviour:

[1] If the ASP page had been stored in the local file system of the IIS
Server, anything works fine. The client immediately sees the change.

[2] If the ASP page had been stored in the file system of another Windows
2003 server, the first refresh does not work. The old content is sent to the
browser. One has to refresh a second time, for getting the new contents.

The wrong result can be seen, even if the following scenario is performed...

- open new browser
- load ASP page
- change the ASP page on the server
- open a new browser
- load the ASP page

After loading the ASP page in a separate browser window, the old contents
can be seen.

Can anybody reproduce this behaviour? Is it already known? Is there a
solution?

Michael G. Schneider

Michael G. Schneider
11/16/2003 3:16:26 PM
"Evertjan." <exjxw.hannivoort@interxnl.net> schrieb im Newsbeitrag
news:Xns9435942B3ABA6eejj99@194.109.133.29...

[quoted text, click to view]


It's probably my bad English. It seems, as if I did not ask my question
correctly. Maybe I should emphasize the following...

- I am sure, that this is no client side feature.

- If it were a client side feature, why should the refresh be immediately
visible, if the ASP page is saved in the IIS local file system?

- If it were a client side feature, why should the refreshed contents be
visible on the second trial, just some milliseconds after the first one?

- The observation cannot be seen under Windows 2000 Server. There the new
contents is always presented. It does not matter, whether the ASP page is
saved in the IIS local file system or on another server.

- I believe it has to do with how IIS in Windows 2003 Server handles virtual
directories located on another server.

Michael G. Schneider

Michael G. Schneider
11/16/2003 4:56:58 PM
"Aaron Bertrand [MVP]" <aaron@TRASHaspfaq.com> schrieb im Newsbeitrag
news:eV%23gFhFrDHA.2528@TK2MSFTNGP12.phx.gbl...
[quoted text, click to view]

These techniques do not work in my scenario. Moreover the browser has the
"search for new versions of a page on each and every access" setting
(translation probably not 100% correct).

Here in my case, it is definitely a question of whether the ASP page is
stored locally or remotely. The good behaviour (local) and the bad behaviour
(remote) can be reproduced any number of times.

If anybody has some time to test this on his 2003-servers, I would be happy
to hear the results.

With Windows 2000 the IIS relied on change notification to find out, whether
a certain ASP page has been modified. Does anybody know, whether this has
changed?

Michael G. Schneider

Mike Florio
11/19/2003 10:27:08 AM
I have seen this under Windows 2000 Server / IIS 5 too. I highly suspect
it's just plain old browser caching ;-)

Here's what you should try (I amended your list) :

- open new browser
- load ASP page
- change the ASP page on the server
- *** CLOSE BROWSER ***
- open a new browser
- load the ASP page



[quoted text, click to view]

Mike Florio
11/19/2003 12:33:47 PM
I only tested that scenario under 2000 server, with virtual dirs *on the
same server*, and the close/open browser worked in that case.

When you try from another pc, is it on the same network ? Have you tried
accessing the site from an external ip ?


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Michael G. Schneider
11/19/2003 6:02:46 PM
"Mike Florio" <mike@micro-point.com> schrieb im Newsbeitrag
news:vrn2tsm5sgpv32@corp.supernews.com...

[quoted text, click to view]

No, unfortunately it is not browser caching

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Ok, I tried, I even tried some more as...

- open new browser
- load ASP page
- change the ASP page on the server
- CLOSE BROWSER
- OPEN BROWSER
- DELETE COOKIES
- DELETE TEMPORARY FILES
- DELETE HISTORY
- CLOSE BROWSER
- open a new browser
- load the ASP page

I even tried more...

- open new browser
- load ASP page
- change the ASP page on the server
- GO TO ANOTHER PC
- open a new browser
- load the ASP page

And yes, the loading the ASP page after it has been modified, still shows
the old contents. The ASP page has to be requested twice, in order for the
new contents showing up.

Did you actually test this scenario (virtual directory on another 2003
server)?

Michael G. Schneider


Michael G. Schneider
11/19/2003 8:03:28 PM
"Mike Florio" <mike@micro-point.com> schrieb im Newsbeitrag
news:vrnabb5bh48pe3@corp.supernews.com...

[quoted text, click to view]

I have been using the 2000 server scenario for years. I do know that it
works.

[quoted text, click to view]

This is a small network. Three Windows 2003 servers, some workstations. All
belong to the same domain.

No I did not try it from outside. I have to make it work in this network,
anyway. This feature is very disturbing, when it comes to testing an ASP
application. There you often change an ASP page, and one wants to see the
results immediateley, and not after hitting submit twice.

Michael G. Schneider

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