It seems that .net core needs to be published to run on IIS which means it's either impossible or impractical to debug through IIS, but it's fine with IIS Express. My more experienced colleagues insist that we should do all development with IIS and never IIS Express which is, in effect, saying we should not touch .Net Core.
1) How likely am I to find that the app which works on IIS Express doesn't work on IIS?
2) What's the best way to mitigate the downsides?
3) What should I tell my boss? (I really want to keep working with core)
There is no reason not to debug using IIS Express. You can verify that your deployment works on IIS by publishing to a staging environment or even a local IIS instance.
That being said, it is possible to debug IIS locally by using Attach to Process in Visual Studio if your coworkers simply refuse to use IIS Express.
Its a big difference between iis express and iis(server). on iis server you need to configure first the iis itself. register asp.net, set up .net framework,set up config file and so on..
But this would be a good practice for the developer, iis server deployment process. is a must.
Hope it helps your idea..
When working with ASP.NET Core & Visual Studio IDE, its better to use IIS Express (kestrel internally) for following reasons
Kestrel is a light weight web server built for ASP.NET Core apps. IIS Express will make use of it while development & debugging.
Hosting IIS for ASP.NET Core apps is for providing load balancing, SSL, gzip etc. So even if you host on IIS, then its fine but development experience will be less productive.
ASP.NET Core apps are cross platform so you can work on Windows, Linux & MacOS. With IIS your are limiting to Windows only
Core apps are not like traditional ASP.NET MVC 5 or Web form apps. They have being made easy for development experience.
I would suggest that think of IIS only during deploying Core apps for QA, UAT or PROD. For development need not host on IIS. Hope this helps
Related
What is the kestrel web server and how does it relate to IIS / IIS Express?
I come from developing apps on IIS Express and hosting them on an IIS web server. With ASP.NET Core I have a dependency on Microsoft.AspNetCore.Server.Kestrel and my startup has .UseServer("Microsoft.AspNetCore.Server.Kestrel"). But when I run my website, I still get the IIS Express icon in the system tray. Someone asked me if I was using IIS Express or Kestrel and I didn't know what to say!
I don't have any cross-platform requirements as I develop on a PC and host in Azure, so I'm confused if I even need Kestrel, but it doesn't seem like there's an alternative - even the simplest samples use Kestrel.
I'd like to offer an alternative answer, with some history, so that you might understand why Kestrel comes, even if you only use Windows and IIS.
At the very beginning of ASP.NET development before year 2000, clearly Microsoft created two pieces to host ASP.NET WebForms apps,
Cassini, later became ASP.NET Development Server in Visual Studio. It is a fully managed web server written in C# based on HttpListener. Of course, since it was for development only, many features were never implemented. As Microsoft made the source code of Cassini available for the public, there are third parties who forked the code base and added more features, which started the Cassini family.
ASP.NET support on IIS (revision 1). Because IIS was 4.0 and 5.0/5.1 at that time, which has nothing like application pools, ASP.NET even has its own worker process (aspnet_wp.exe).
So to develop a web app, you use Cassini, and to deploy you use IIS.
The introduction of application pools in IIS 6 required some changes on ASP.NET side, so aspnet_wp.exe became obsolete and replaced by aspnet_isapi.dll. That can be seen as ASP.NET support on IIS revision 2. So ASP.NET apps are being hosted in IIS worker processes w3wp.exe.
The introduction of integrated pipeline in IIS 7 and above required further changes, which replaced aspnet_isapi.dll with webengine4.dll. That can be seen as ASP.NET support on IIS revision 3. ASP.NET and IIS pipelines are unified.
You can see ASP.NET has become much more complex and tightly integrated with IIS, so Cassini started to show its age, and gradually was replaced by IIS Express (a user mode lite IIS).
Thus, in many cases, when people blame that IIS is slow, they should blame ASP.NET in fact. IIS itself without ASP.NET is pretty fast and stable, while ASP.NET was not developed with enough performance metrics in mind (as WebForms focuses quite a lot of productivities and RAD).
Then in November 2014, ASP.NET 5 (later renamed to ASP.NET Core) was announced and became a cross platform technology. Obviously Microsoft needed a new design to support Windows, macOS, and Linux, where all major web servers, nginx/Apache (or other web servers) should be considered besides IIS.
I think many would agree that Microsoft learned quite a lot from NodeJS, and then designed and developed Kestrel (based on libuv initially but might move to other technology soon). It is a light-weight web server like Cassini initially, but later more features are being added (like another answer commented, much more features so can be treated as a full web server). Though fully managed (some native dependencies exist), it is no longer a toy web server like Cassini.
Then why cannot you just use Kestrel? Why IIS Express and potentially IIS, nginx, or Apache are still needed? That primarily is a result of today's internet practice. Most web sites use reverse proxies to take requests from your web browsers and then forward to the application servers in the background.
IIS Express/IIS/nginx/Apache are the reverse proxy servers
Kestrel/NodeJS/Tomcat and so on are the application servers
Another answer already showed a link to Microsoft documentation, so you can take a look.
Microsoft developed HttpPlatformHandler initially to make IIS a good enough reverse proxy for Java/Python and so on, so planned to use it for ASP.NET Core. Issues started to appear during development, so later Microsoft made ASP.NET Core Module specifically for ASP.NET Core. That's ASP.NET support on IIS revision 4.
Starting from ASP.NET Core 2.2, ASP.NET Core Module for IIS (version 2) can host .NET Core environment inside IIS worker process (w3wp.exe), quite similar to ASP.NET 2.x/4.x. This mode is called "IIS in-process hosting". It can be considered as ASP.NET support on IIS revision 5.
Well, quite lengthy, but I hope I put all necessary pieces together and you enjoy reading it.
One recent update (Jan 2023) is that ASP.NET Core/Kestrel can be used to host reverse proxy functionalities itself, as the open source YARP project revealed.
Kestrel/YARP is now widely used inside Microsoft Azure to replace IIS ARR in many scenarios as reported, so literally now you can host your own production web apps with Kestrel/YARP without any other web server (IIS/nginx/Apache) in front as well.
What is Kestrel
It's a full blown web server. You can run your ASP.NET Core application using just Kestrel.
But when I run my website, I still get the IIS Express icon in the system tray
In your ASP.NET application, probably in the wwwroot directory, you'll see a web.config that contains this:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<system.webServer>
<handlers>
<add name="httpPlatformHandler" path="*" verb="*" modules="httpPlatformHandler" resourceType="Unspecified"/>
</handlers>
<httpPlatform processPath="%DNX_PATH%" arguments="%DNX_ARGS%" stdoutLogEnabled="false" startupTimeLimit="3600"/>
</system.webServer>
</configuration>
This is the HttpPlatformHandler. Essentially, what this does is forward all requests to Kestrel. IIS Express (and IIS for that matter) will not run ASP.NET themselves anymore. Instead, they will act as proxies that simply pass requests and responses back and forth from Kestrel. There is still advantages of using IIS, specifically it gives you security configuration, kernel-level caching, etc.
From ms docs at:
https://learn.microsoft.com/en-us/aspnet/core/fundamentals/servers/kestrel?tabs=aspnetcore2x
Kestrel is a cross-platform web server for ASP.NET Core based on
libuv, a cross-platform asynchronous I/O library. Kestrel is the web
server that is included by default in ASP.NET Core project templates.
You can use Kestrel by itself or with a reverse proxy server, such as
IIS, Nginx, or Apache. A reverse proxy server receives HTTP requests
from the Internet and forwards them to Kestrel after some preliminary
handling.
UPDATE: .net core 2.1, Kestrel uses managed sockets instead of libuv
From asp.net core 2.1 docs at: https://learn.microsoft.com/en-us/aspnet/core/fundamentals/servers/kestrel?view=aspnetcore-2.1#transport-configuration
With the release of ASP.NET Core 2.1, Kestrel's default transport is
no longer based on Libuv but instead based on managed sockets.
Multiple apps on the same port is not supported in Kestrel.
Windows Authentication does not exist on Kestrel.
Request Filtering is much more fully featured in IIS.
Mime Type Mapping is much better in IIS.
HTTP access logs aren’t collected in Kestrel.
For now I'm just have a little experience in web development. So, cannot be sure in second decision.
I'm restricted by .NET 4.0, ASP.NET MVC4 and IIS 7.0 for application deploying.
Can i include to my MVC project XSockets.NET library?
Disturbs note on the main page Note: We do not recommend to host XSockets inside of IIS in test/production due to the fact that IIS recycles. Which version Windows Server i restricted also ?
As per Uffe's First comment.
If you do not use state in XSockets you do not need to worry about
the IIS recycle. Just use XSockets inside of IIS and rock on. If you
use state in XSockets I would recommend you to use the windows
service, azure, amazon, console app etc...
I am developing a web application. My code worked fine on the WebDev server in VS2010. Then, I hosted it on remote IIS, because my windows 7 home basic doesn't have IIS, and almost all code fails. So I had to rewrite it using helpers for links, ResolveUrl and many other functions.
How can I host an application while debugging on remote IIS (not on WebDev or local IIS) automatically?
You can install IIS Express. IIS express is more mature in terms of emulating real IIS 7. For more information on IIS express refer this link. HTH
You might consider developing you application using MebMatrix, which is a free development environment that includes IIS Express. It's easy to learn and doesn't require Visual Studio.
I'm deploying an ASP.NET application to Windows Server 2003 under IIS
IIS is serving html pages fine but I get a page not found when I try and serve IIS pages
You may need to "register" IIS for ASP.NET applications. As an administrator, run the command "%systemroot%\Microsoft.NET\Framework\v2.0.50727\aspnet_regiis -i". In addition, you may need to convert your web site to an application through the IIS management console.
By default, IIS has ASP support disabled in IIS6.
A server running a member of the Microsoft® Windows® Server 2003 family supports application server functionality, with Microsoft ASP.NET as an option that you can enable when configuring the application server role. To deploy ASP.NET Web applications to a production server, you must be sure to enable the ASP.NET and Internet Information Services (IIS) roles on the production server before you distribute the application.
See here for instructions to enable it:
http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/9fc367dd-5830-4ba3-a3c9-f84aa08edffa.mspx?mfr=true
Other possible reason could be Web Service Extensions, where ASP.NET version could have been disabled. My other post here explains steps to solve this.
Make sure the right .NET framework is installed properly
Make sure the ASP.NET extension is enabled
Under website properties, ASP.NET tab, make sure the right version is set.
After having this same issue and trying all of the above without any luck. We reinstalled SP2 for Windows 2003 and this resolved our issue. I too have seen this problem resolved a few times with the other answers. Most of the time just reinstalling .Net 2.0 resolves the issue but not this time.
For future reference, this could also be the issue:
IIS on a Windows Server 64-bit can only to run in either 32 or 64 bit mode.
In short you need to:
1) run adsutil.vbs to enable 32 bit asp.net apps on win 64
2) re-register IIS calling aspnet_regiis.exe
3) re-open IIS Manager, go into Web service extension list and ensure ASP.Net version {2/4.xxx} (32-bit) is set to Allowed
(You might need to do Steps 2 and 3 for both Framework 2.0 and 4.0 if you want to run asp.net apps on both versions)
Full details are in the following link: http://support.microsoft.com/kb/894435
Another future reference in case this is helpful to anyone who used a similar path to mine.
My back end for the ASP.NET app was MySql not Sql Server, which for me meant having a mysql connector, the reason my IIS was not serving the .aspx file is because on my development environment I was using a different version of the MySql connector than the one installed on my production environment, I updated the MySql connector on the production server to match the version Im using on the development environment and it worked great.
I want to test ASP.NET applications to get the feel for the MVC extension and compare that to what I can do today with Grails or Rails.
The trouble is that being in a corporate environment, I can't install IIS on my workstation, neither on my DEV server. And - you guessed it - Visual Studio is not to be considered at that moment (I guess for my investigations I'll stick with SharpDevelop and the .NET SDK for the time being).
On the Java side, I could unzip some Tomcat distribution in any folder and hit go.
Is there any equivalent in the IIS world, like a lightweight ASP.NET host?
Thanks,
Rollo
UltiDev Cassini Web Server
cassini runs locally. I'll get a link..
Edit: Here's the link to the Cassini Web Server
UltiDev recently started shipping test builds of the Cassini replacement - UltiDev Web Server Pro. It requires elevated/admin privileges to be installed, but it can be downloaded for free. It's quite advanced, it's closer to IIS than Cassini. See screenshots.