IIS caching output of pages

  • Thread starter Thread starter Nick Gilbert
  • Start date Start date
N

Nick Gilbert

Hi,

Our development web server (Win 2003 Server) seems to be caching the
output of various files (CSS and .aspx files) if they have no query
string. The moment you put a question mark in the URL, it's fine.

The problem is that if you modify a file, it still shows you the old
file unless you restart the website or IIS itself. It's definitely not
the browser that's caching the files - IIS is actually serving the wrong
file.

Is there some way to disable this? Why doesn't IIS realise when the file
on it's local filesystem has been modified and reload it?

I had a similar problem once before where my workstation had it's clock
a few minutes into the future, but this time it seems to be a different
problem as now all our machines are synchronised and are set to exactly
the same time.

I'd be greatful if someone can tell me how to solve this very annoying
problem.

Thanks,

Nick...
 
Nick Gilbert said:
Our development web server (Win 2003 Server) seems to be caching the
output of various files (CSS and .aspx files) if they have no query
string. The moment you put a question mark in the URL, it's fine.
Click to expand...

Have you proven its your webserver and not the browsers, or proxies?
 
Hi Nick,


Thanks for posting in the community!
From your description, you found that the files on your IIS Serve such as
(css or aspx files) are always cached and won't be the latest version if it
is modified and requested by client unless appending querystring after the
request url, yes?
If there is anything I misunderstood, please feel free to let me know.

Based on my experience, the such static files and resources such as images,
css files , js files ...etc are all by default cached on the client in the
temporary foler rather than on the serverside. For example, if a user visit
a certain page and the page contains some images and refernce some certain
css or js files. Then the browser will download these resources and cached
in the local disk and next time the page is refreshed (request again) these
resoures files won't be downloaded again from serverside but retrieved from
local cache disk.
So as for your situation, I think the problem you met is likely caused by
the client's cache. And as you've mentioned that this can be avoided( force
the browser to download the file from serversdie everytime the page is
requested) if you append a querystring(need to be different everytime)
after the page's url. So if you'd like the page's refernced resources files
to be downloaded everytime from serverside(the latest version), I think you
can append a tempstamp as querystring after the certain resource file's
url. For example,
if we use a css file as below:
src="common.css"
then now, we replace it as this:
src="common.css?version=<% timestamp %>"

Thus, everytime the page is requested, the css file will be retireved from
serverside (its latest version). How do you think of this?

In addition ,here are some tech articles on browser's cache:
#HOWTO: Prevent Caching in Internet Explorer
http://support.microsoft.com/?id=234067

#How to Use Pragma: No-cache with IIS and IE
http://support.microsoft.com/?id=165150

Hope they're also helpful.



Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
 
Thanks Steven, but it's definitely IIS that's caching the web pages -
not the client. We have verified this by disabling caching in IE,
looking at the pages from other machines or browsers and by telnetting
into the server and looking at the raw HTTP response (which shows the
old data). The *only* way to force the new page to display, is to
restart the website in IIS or reboot the whole server.

Why is IIS (or the file system) caching the pages and how can we stop
this?

Nick...
 
Hi Nick,


Thanks for your response. Based on my further research, there does seems to
have a certain issue on the IIS Server, but it is used to focus on win2000
server, here is the kb article on it:

#FIX: IIS Does Not Refresh the File Cache for Non-Virtual Root Directories
http://support.microsoft.com/?id=329459

Please have a check to see whether it could provide some help or clues on
this issue. In addtion, I've searched some other articles on setting cache
via page's http header:

#How to Modify the Cache-Control HTTP Header When You Use IIS
http://support.microsoft.com/?id=247404

#HOW TO: Prevent Web Caching in Windows 2000
http://support.microsoft.com/?id=311006


Hope they're also helpful.


Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
 
Thanks, but these articles pertain to Windows 2000 and we are actually
running Windows Server 2003 Standard Edition. We are still
experiencing this problem so if you have any other ideas, please let
me know!

Nick...
 
Hi Nick,

Thank you for the response. Regarding on the issue, I am
finding proper resource to assist you and we will update as soon as posible.

Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security(This posting is provided "AS IS",
with no warranties, and confers no rights.)
 
Hi Nick,

After further research, I found that there seems an issue on IIS6's
caching, here is the detailed description on it:

----------------------------------------------------------------
In Microsoft Internet Information Services 6.0, if your Web site is
configured for both an IP address and host headers, any change that you
make to the static content does not appear immediately.

CAUSE
=====

This problem occurs because of the way that the content is stored in the
Http.sys cache.

RESOLUTION
==========

Hotfix information
------------------
A supported hotfix is now available from Microsoft, but it is only intended
to correct the problem that is described in this article. Only apply it to
systems that are experiencing this specific problem. This hotfix may
receive additional testing. Therefore, if you are not severely affected by
this problem, Microsoft recommends that you wait for the next Windows
Server 2003 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support
Services to obtain the hotfix. For a complete list of Microsoft Product
Support Services phone numbers and information about support costs, visit
the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS:
http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS

Note In special cases, charges that are ordinarily incurred for support
calls may be canceled if a Microsoft Support Professional determines that a
specific update will resolve your problem. The usual support costs will
apply to additional support questions and issues that do not qualify for
the specific update in question.


Restart requirement

You must restart your computer after you apply this hotfix


File information
The English version of this hotfix has the file attributes (or later) 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 tool in
Control Panel.

Date Time Version Size File name
------------------------------------------------------
10-Dec-2003 00:37 5.2.3790.110 334,336 Http.sys
10-Dec-2003 01:18 5.2.3790.110 27,648 Httpapi.dll
10-Dec-2003 01:18 6.0.3790.110 338,432 W3core.dll

Note If you are also experiencing the symptoms that Microsoft Knowledge
Base article 832911 describes, apply this hotfix before you apply hotfix
832911.

--------------------------------------------------------

However, this issue is still in testing. Not sure whether your problem due
to it.

In addtion, you should also verify whether or not this is a kernel mode
caching issue you're dealing with by temporarily disabling the kernel mode
cache (UriEnableCache=0, etc.). For details on this, refer to
http://support.microsoft.com/?id=820129.

Please check out the above items. Hope they are helpful.


Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
 
Steven,

Thanks, but the post does not include the URL of the hotfix, and the KB
article ID it refers to doesn't exist (832911). In fact there doesn't
seem to be a section on the knowledge base at all for IIS 6 - it stops
at IIS 5. If this is a known problem, then surely I shouldn't have to
pay to get a simple hotfix? Additionally, do you know the URL or ID of
the article that you posted (as below) as I can't find that on the
knowledge base either.

Thanks,

Nick...
Hi Nick,

After further research, I found that there seems an issue on IIS6's
caching, here is the detailed description on it:

----------------------------------------------------------------
In Microsoft Internet Information Services 6.0, if your Web site is
configured for both an IP address and host headers, any change that you
make to the static content does not appear immediately.

CAUSE
=====

This problem occurs because of the way that the content is stored in the
Http.sys cache.

RESOLUTION
==========

Hotfix information
------------------
A supported hotfix is now available from Microsoft, but it is only intended
to correct the problem that is described in this article. Only apply it to
systems that are experiencing this specific problem. This hotfix may
receive additional testing. Therefore, if you are not severely affected by
this problem, Microsoft recommends that you wait for the next Windows
Server 2003 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support
Services to obtain the hotfix. For a complete list of Microsoft Product
Support Services phone numbers and information about support costs, visit
the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS:
http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS

Note In special cases, charges that are ordinarily incurred for support
calls may be canceled if a Microsoft Support Professional determines that a
specific update will resolve your problem. The usual support costs will
apply to additional support questions and issues that do not qualify for
the specific update in question.


Restart requirement

You must restart your computer after you apply this hotfix


File information
The English version of this hotfix has the file attributes (or later) 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 tool in
Control Panel.

Date Time Version Size File name
------------------------------------------------------
10-Dec-2003 00:37 5.2.3790.110 334,336 Http.sys
10-Dec-2003 01:18 5.2.3790.110 27,648 Httpapi.dll
10-Dec-2003 01:18 6.0.3790.110 338,432 W3core.dll

Note If you are also experiencing the symptoms that Microsoft Knowledge
Base article 832911 describes, apply this hotfix before you apply hotfix
832911.

--------------------------------------------------------

However, this issue is still in testing. Not sure whether your problem due
to it.

In addtion, you should also verify whether or not this is a kernel mode
caching issue you're dealing with by temporarily disabling the kernel mode
cache (UriEnableCache=0, etc.). For details on this, refer to
http://support.microsoft.com/?id=820129.

Please check out the above items. Hope they are helpful.


Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
Click to expand...
 
Hi Nick,

Thanks for your response. As for the KB, since it is still under reviewing
so we can't get it via the public url. And about the hotfix, it has been
mentioned in it that you need to call the PSS for it:
------------------------------------------------
To resolve this problem immediately, contact Microsoft Product Support
Services to obtain the hotfix. For a complete list of Microsoft Product
Support Services phone numbers and information about support costs, visit
the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS:
http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS

---------------------------------------------------
So the url only provide the address to find the contact info of the PSS.

In addition, have you also checked another suggestions in my former reply?
-------------------------------
In addtion, you should also verify whether or not this is a kernel mode
caching issue you're dealing with by temporarily disabling the kernel mode
cache (UriEnableCache=0, etc.). For details on this, refer to
http://support.microsoft.com/?id=820129.
---------------------------------

Thanks.


Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
 
Hello-

I'd like to add to this post since I am having the same issue as
described above. Here are my server and development box specs:

Server:
Win 2k3 (was upgraded from 2k, not a fresh install)
IIS 6
..Net 1.1

Dev Box:
Win 2k3
IIS 6.0
..Net 1.1
VS.Net 2k3

I have been working on this issue for most of day (lots of googling)
and have yet to find a solution. Here is a recap of the details of how
i'm seeing this issue.

Created a c# web app project in vs.net. The site is a sub domain,
sub.mysite.com I have an aspx file called default.aspx in a sub folder
that is linking to a css sheet within the same folder as the aspx
file:
<link rel="stylesheet" type="text/css" href="more04/default.css">

I can make changes to the aspx file all day long, and see the changes
instantly every time. However, when it comes to the default.css file,
i cannot see my changes as i make them. When i stop/start iis, and
refresh my browser, i see the change. then i can make a change, and
when i refresh, i see it. but then when i make another change, i
refresh, and do not see the change. When i go to the css page in IE, i
get the old file. When i RDC into the web server, and open the file
into text pad, i see the file that should be served to the browser.
This tells me that it is an IIS caching issue, not an IE issue.

I've tried nearly everything i can think of, with the exception of
rebuilding the web server. I've ensured that IE is asking for a new
file on every request, i've tried to disable asp caching, i've tried
turning off buffering, but nothing seems to work.

I seem to remember a situation very much like this about 2 years ago
when i first started .net development for another company, and seem to
remember that the fix was to make a change to the registry. I've
searched high and low, and have yet to find anything that works.

Steve, it would be great if you could get someone in this group that
could post a link to the hotfix so we could give it a try. I would
also like some more info on the possible downsides to this patch so I
have an idea of what to look for if it damages other parts of iis.

Thanks

Levi Rosol
http://www.iveldesigns.com

Nick Gilbert said:
Steven,

Thanks, but the post does not include the URL of the hotfix, and the KB
article ID it refers to doesn't exist (832911). In fact there doesn't
seem to be a section on the knowledge base at all for IIS 6 - it stops
at IIS 5. If this is a known problem, then surely I shouldn't have to
pay to get a simple hotfix? Additionally, do you know the URL or ID of
the article that you posted (as below) as I can't find that on the
knowledge base either.

Thanks,

Nick...
Hi Nick,

After further research, I found that there seems an issue on IIS6's
caching, here is the detailed description on it:

----------------------------------------------------------------
In Microsoft Internet Information Services 6.0, if your Web site is
configured for both an IP address and host headers, any change that you
make to the static content does not appear immediately.

CAUSE
=====

This problem occurs because of the way that the content is stored in the
Http.sys cache.

RESOLUTION
==========

Hotfix information
------------------
A supported hotfix is now available from Microsoft, but it is only intended
to correct the problem that is described in this article. Only apply it to
systems that are experiencing this specific problem. This hotfix may
receive additional testing. Therefore, if you are not severely affected by
this problem, Microsoft recommends that you wait for the next Windows
Server 2003 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support
Services to obtain the hotfix. For a complete list of Microsoft Product
Support Services phone numbers and information about support costs, visit
the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS:
http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS

Note In special cases, charges that are ordinarily incurred for support
calls may be canceled if a Microsoft Support Professional determines that a
specific update will resolve your problem. The usual support costs will
apply to additional support questions and issues that do not qualify for
the specific update in question.


Restart requirement

You must restart your computer after you apply this hotfix


File information
The English version of this hotfix has the file attributes (or later) 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 tool in
Control Panel.

Date Time Version Size File name
------------------------------------------------------
10-Dec-2003 00:37 5.2.3790.110 334,336 Http.sys
10-Dec-2003 01:18 5.2.3790.110 27,648 Httpapi.dll
10-Dec-2003 01:18 6.0.3790.110 338,432 W3core.dll

Note If you are also experiencing the symptoms that Microsoft Knowledge
Base article 832911 describes, apply this hotfix before you apply hotfix
832911.

--------------------------------------------------------

However, this issue is still in testing. Not sure whether your problem due
to it.

In addtion, you should also verify whether or not this is a kernel mode
caching issue you're dealing with by temporarily disabling the kernel mode
cache (UriEnableCache=0, etc.). For details on this, refer to
http://support.microsoft.com/?id=820129.

Please check out the above items. Hope they are helpful.


Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
Click to expand...
Click to expand...
 
ok, double post time....

I have found the solution to my problems! at least with this iis
caching problem.

first, Steve, the last thing in your post was the solution:
"In addtion, you should also verify whether or not this is a kernel
mode
caching issue you're dealing with by temporarily disabling the kernel
mode
cache (UriEnableCache=0, etc.). For details on this, refer to
http://support.microsoft.com/?id=820129."

second, if you read in that article, you will see a list of reg
entries that can be made for IIS. when i checked those settings on my
server, the only item i had was: DisableServerHeader and it has a
value of 1. I then added UriEnableCache dword, and set it to 0.
stop.start iis, and bingo! my changes are real time!

hopefully this problem becomes easier to fix for others since i've
actually responded to the google groups with a solution. it drove me
crazy today finding all of these articles about issues like i was
seeing, but without a good solid response.

Thanks
Levi

Nick Gilbert said:
Steven,

Thanks, but the post does not include the URL of the hotfix, and the KB
article ID it refers to doesn't exist (832911). In fact there doesn't
seem to be a section on the knowledge base at all for IIS 6 - it stops
at IIS 5. If this is a known problem, then surely I shouldn't have to
pay to get a simple hotfix? Additionally, do you know the URL or ID of
the article that you posted (as below) as I can't find that on the
knowledge base either.

Thanks,

Nick...
Hi Nick,

After further research, I found that there seems an issue on IIS6's
caching, here is the detailed description on it:

----------------------------------------------------------------
In Microsoft Internet Information Services 6.0, if your Web site is
configured for both an IP address and host headers, any change that you
make to the static content does not appear immediately.

CAUSE
=====

This problem occurs because of the way that the content is stored in the
Http.sys cache.

RESOLUTION
==========

Hotfix information
------------------
A supported hotfix is now available from Microsoft, but it is only intended
to correct the problem that is described in this article. Only apply it to
systems that are experiencing this specific problem. This hotfix may
receive additional testing. Therefore, if you are not severely affected by
this problem, Microsoft recommends that you wait for the next Windows
Server 2003 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support
Services to obtain the hotfix. For a complete list of Microsoft Product
Support Services phone numbers and information about support costs, visit
the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS:
http://support.microsoft.com/default.aspx?scid=fh;[LN];CNTACTMS

Note In special cases, charges that are ordinarily incurred for support
calls may be canceled if a Microsoft Support Professional determines that a
specific update will resolve your problem. The usual support costs will
apply to additional support questions and issues that do not qualify for
the specific update in question.


Restart requirement

You must restart your computer after you apply this hotfix


File information
The English version of this hotfix has the file attributes (or later) 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 tool in
Control Panel.

Date Time Version Size File name
------------------------------------------------------
10-Dec-2003 00:37 5.2.3790.110 334,336 Http.sys
10-Dec-2003 01:18 5.2.3790.110 27,648 Httpapi.dll
10-Dec-2003 01:18 6.0.3790.110 338,432 W3core.dll

Note If you are also experiencing the symptoms that Microsoft Knowledge
Base article 832911 describes, apply this hotfix before you apply hotfix
832911.

--------------------------------------------------------

However, this issue is still in testing. Not sure whether your problem due
to it.

In addtion, you should also verify whether or not this is a kernel mode
caching issue you're dealing with by temporarily disabling the kernel mode
cache (UriEnableCache=0, etc.). For details on this, refer to
http://support.microsoft.com/?id=820129.

Please check out the above items. Hope they are helpful.


Regards,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

Get Preview at ASP.NET whidbey
http://msdn.microsoft.com/asp.net/whidbey/default.aspx
Click to expand...
Click to expand...
 
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