If we use an aspx page with a Caching Profile, the server caches images that are loaded with the aspx page. So if ten clients load the same image through the aspx page (same url), for one client the image is gotten out of the db, for the nine others it is cached.
When we use a HttpHandler, this doesn't happen. The image is always fetched from the database. We have tried all different settings without any success. (we have checked this link and have not been able to cache on server side).
I can't answer based on experience of using the caching profile, so I'm not sure if this helps.
Under the covers, ASP.NET WebForms are driven by HttpHandlers - written by MS (as you'd expect). When you write you own Http Handler you don't automatically get all the functionality that the System.Web.UI.PageHandlerFactory handler has (the one that by default looks after .aspx pages/requests) - you have to bring it in (or develop it) yourself.
Maybe this is the problem you have - maybe the Caching Profile capabilities are being leveraged by the aspx pages because the System.Web.UI.PageHandlerFactory is already "integrated" with it out of the box, where-as when you write your own they just aren't there (by default) - and hence the they don't work.
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We have a Sitecore/Webforms based website that we'd like to run behind Akamai CDN however we're having an issue with ViewState MAC validation on our postbacks.
We've worked around this for most of the core forms on the site (by taking them out of the CDN cache and serving them direct for every user), but we're left with a simple form in the footer of every page that posts back to the server.
Currently we're seeing errors:
Validation of viewstate MAC failed.
I believe this is caused by the CDN caching the viewstate fields from the original request and these (obviously) not matching for other users.
As we are running this site on multiple servers, we already have the machinekey correctly configured (we've been able to use postBackUrl settings to post back to other pages/SSL instances/etc.) before we added Akamai.
As we're running Asp.NET 4.5.2 there's no way we can even attempt to disable viewstate MAC even if we thought it was a good idea.
Setting ViewStateMode=Disabled still leaves us with a tiny viewstate (presumably the MAC) which still causes problems.
Is there anyway we can remove the session dependence from the viewstate?
The basic steps we can use to replicate this:
Request page from Browser A - Akamai caches page.
Submit form from Browser A - Success!
Request page from Browser B - Akamai serves cached page.
Submit form from Browser B - ERROR!
Nope, Akamai CDN never caches POST requests. But its good idea to try adding the forms to do not cache list and try replicate the issue.
My setup: ASP.NET 4.0 Web Site running on IIS 6.0.
I have a site with many landing pages with virtual URLs, all being served by a single physical landingpage.aspx file (via ASP.NET 4.0 Routing), in which I use the OutputCache directive, caching the page on the server for 24 hours.
Recently, I started to experience a problem that the __doPostBack JavaScript block was missing from some of the generated pages. There is a LinkButton in the page (inside a webusercontrol), so the JS block should be there, but sometimes it isn't. This is naturally leading to JS errors in the browser upon clicking the LinkButton.
My suspicion is that maybe on the first visit to a given URL handled by the above mentioned physical .aspx file it might have been a visit by a client (a browser or a search bot) which maybe was considered by ASP.NET as a down-level browser, and therefore the doPostBack was not output into the generated cached version of the page, and then this wrong cached version is served to all the subsequent visitors...? On the other hand, I'd say ASP.NET is smart enough to generate different cached version for different levels of browsers, isn't it?
Nevertheless, my question is: can I find the cached files that are served to the visitors somewhere on the server, and somehow check if my assumptions are correct? Also, I would like to disable this ASP.NET recognition of browsers altogether and serve the same content to every browser, just as it would serve to any modern browser.
Thanks a lot for any advice and help.
Answering my own question: Confirmed that the website was sending back HTML without __doPostBack() for unrecognized browsers. Adding ClientTarget="uplevel" to the # Page directive at the top of the .aspx page in question solved the problem and __doPostBack() block is now always present.
I work on a web application in ASP.NET and HTML5. I have a simple page Default.aspx. In its Page_Load handler I call 'Response.Redirect("xxx.aspx"). I also defined a manifest file, Default.appcache as I want my application to work offline (in such case I javascript methods are used for redirection). Browser cached the page as expected but a problem occured - even though server is online, browser uses the cached page. When user enters Default.aspx no call is sent to server. How can I prevent this behavior? I would like the browser to send a normal request to IIS if it is online and use cached page only when server doesn't respond.
I would be grateful for all suggestions.
You can't, pages in the cache are always served from the cache. The only way to update them is update the manifest and force new versions to be downloaded.
If you want one page to be served when online and a different one when offline then you should investigate the FALLBACK section of the manifest. Note that the page which references the manifest is always cached, so you need to set the fallback up on a different pair of pages.
I'm moving an old VBScript web site over to ASP.NET, so I'm starting to use master pages instead of #includeing lots of other files with server side VBScript in them.
How can I stop the pages (as in the ones that are based on master pages) from being generated once and then stored? If I make a change to the master page (or any page based on them) those changes are not visible, because the web server is still giving out the previous versions.
It sounds like you have caching enabled, as normal behaviour without caching is to regenrate.
That shouldn't be the case, are you sure it's not a caching issue?
I set up 404 handler page in web.config, but it works ONLY when extension of URL is .aspx (or other which is handled by ASP.NET).
I know I can setup static HTML page in website options, but I want to have a page.
Is there any options to assign ASPX handler page for all request extensions in IIS?
The direct question was whether or not there are options to assign the ASPX handler to all request extensions: Yes, there is. I'll discuss how to do that shortly.
First, I think the "hidden" question -- the answer you really want -- is whether or not there's a way to redirect all 404 errors for pages other than ASPX, ASMX, etc. Yes, there is, and this is the better choice if it'll solve the issue you're having.
To redirect all 404s in IIS 6, right click your web application root (whether it be its own site or a virtual directory in the main site), and choose "Properties." From there, choose the "Custom Errors" tab. Find 404 in the list and change it to the redirect you want.
Now, if that won't suffice -- and I really hope it does -- yes, you can run every page through the ASPX handler. However, doing so comes at a fairly high cost in terms of efficiency -- raw HTML/image serving is considerably faster than anything dynamic.
To do this, right click your web application root and choose "Properties." Choose the "Home Directory" tab. Click "Configuration;" a new window will pop up. Copy the path from one of the ASP.NET page serves, and then use it for a wildcard application map.
Bear in mind, again, this is the wrong answer most of the time. It will negatively impact your performance, and is the equivalent of using a chainsaw to carve a turkey. I highly recommend the first option over this one, if it will work out for you.
For information:
This is one of the several nice things that IIS7 brings - all pages are routed through the handler such that you can do custom 404s and - usefully - directory and file level security for any file (based on the same web.config stuff as for asp.net files prior to IIS7).
So notionally "use II7" is an answer (will be "the" answer in time) - but of course its not a terribly practical one if you're not hosting/being hosted on W2k8 (or higher).
The web.config can only set up errors pages for pages controlled by it's web site. If you have any other pages outside the purview of the ASP.Net application, then you set up handling for them in IIS. There's an option in there for configuring the 404 page where you can point it to your custom page.
Only other thing i can think of is passing ALL extensions to asp.net.
This way all types of files get processed by asp.net and your custom error page will work.
In the IIS application configuration, you can set a wildcard mapping (".*") to C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\aspnet_isapi.dll
You can setup wild card mapping in IIS (Application configuration/Mappings/Wildcard mappings/ - just set aspnet_isapi.dll as executable and uncheck the Verify that file exists box) that will route all incoming requests to your app - so you can control the behavior directly from it.
You don't have to setup static page in your IIS application settings. Imho, you should be able to setup valid url (e.g. /error_handler.aspx) from your app that will be used as landing page in case of specific server error.
In IIS you can set a Custom Error for 404 errors and direct it to a URL in the site properties.
It shows a static html by default
C:\WINDOWS\help\iisHelp\common\404b.htm
You can change it to a relative url on your site.