Debug Your ASP.NET Application that Hosted on IIS : Process Attach and Identify which process to attach . This article will give you the basic understanding of Debugging ASP.NET Application that is hosted on Local Server, along with Process selection among multiple processes. And article was all about if you have IIS installed in local server, that means you have hosted your site on your local development environment or your Web server/ production server having visual studio installed. But this is not the real scenario.
Now coming back to this article, this article is all about the IIS remote debugging. You are developing your application in you local system which is hosted on remote web server and now you need to debug it. How will you do that ? This article will describe all the necessary steps like how to configure remote debugging, attaching process from remote server, start debugging etc. This is one of the most challenging task in ASP.NET.
Visual Studio Internal Debugger
Local IIS Debugging
Remote IIS Debugging
ASP.NET debug enginewhich is used to debug our ASP.NET web application while we are developing it. The process which is used to debug the application within visual studio is
WebDev.WebServer.Exe. ASP.NET Engine uses
WebDev.WebServer.exeto debug the application.
Now if you want to know more details about it please read this .
Fig: Block Diagram for Visual Studio Internal Debugger
Fig: Block Diagram for Debugging ASP.NET site from Local IIS Server
In local IIS debugging, IIS should be installed in the local system where we have visual studio installed. For debugging the application hosted on IIS from visual studio, we need to attach the worker process (
w3wp.exe) with in visual studio. After that we will able to start the debugging of the web application.
This is the main topic which we should cover in this article. It is one of the best features and it is very much helpful when we do not have a IIS Server installed in local system or when we have to store the applications at a centralized location. The scenario comes when you are having with your application code in your system and the build which was deployed on different IIS server. Below diagrams shows the overall diagram for remote debugging.
Fig: Block Diagram for Remote debugging of ASP.NET Application
Remote debugging with Visual studio and Remote IIS is very easy to setup. The tool which is used to setup and configure the process is know as
"msvsmon.exe". I have describe each and every steps to start, configure the msvsmon tool and debug the application. But before that just have a look on why should we need remote debugging.
Before going into details, we need to know when we have to use remote debugging,
Local development server does not have IIS installed.
Development server and Build/Released/Hosting Server is different
Application located in centralized location.
The tool which is used to remote debugging of the ASP.Net application know as "
Msvsmon.exe" . The Remote Debugging tool (
Msvsmon.exe) is a small windows based application that Visual Studio 2005 uses for remote debugging. It has very simple UI which makes it very simple to setup and configure During remote debugging, Visual Studio 2005 runs on one computer and the Remote Debugging Tool runs on the remote computer along with the application you are debugging.
Fig: Block Diagram for Remote debugging of ASP.NET Application with msvsmon
If we want to debug the application which is hosted on remote IIS, we have to start the msvsmon.exe to the remote server, and our development system is the debugger host where we will debug our code.
Install path\Microsoft Visual Studio 8\Common7\IDE\Remote Debugger\x86
Fig: Initial startup of msvsmon.exeAt the time of starting of application the window will show the status message
"Msvsmon started a new server named ''. Waiting for new connection". Which means Debugging monitor tool is ready to connect with some remote server. Now I can connect with this remote server and get the list of all process that is running on the server.
"Tool" > "Options". Following window will appear,
Fig: Setup and configure security settings
Now we have a permission button along with the windows authentication radio button. Using that, we can give permission to any user who belongs to that windows group. If we click on the Permission button, following screen will appear
Fig: Add user for windows authenticationBy default, Administrator should have the permission for remote debugging, we can use add button to add new user and can give the Debug access or Deny the Debug persmission to any user. For example, I have added myself by just clicking on Add button and take the access control.
Fig: Add user for windows authentication
Now, I have give me the permission for debugging from remotely (from Debugger Host).
Fig: Debug permission for selected userSimiliarly we can select any user from Active Directory and can deny the request for remote debugging though the user is Windows authenticated user.
I have discussed about how to debug remotely with windows authentication mode in the process attache section.
There is no security involved with this authentication mode. Any one can debug remotely, if the authentication mode is set to
"No-Authentication". As this debugging mode is not at all secure, so it should be used only on secure network.
Fig: No-Authentication Mode ConfigurationNo Authentication mode only supports native debugging. You can also guess the behaviour from the warning message. We have a "
Allow any User to Debug" check box. If we checked that one, any user can able to debug.
In the next section I have described, how to attach the process for remote debugging for both Windows and No Authentication Mode.
Now, Remote Debugger is ready to accept a new connection to start remote debugging. And we have already gone through how to configure the msvsmon for both windows and No-Authentication mode. Now we will check how to connect with them and start debugging,
Before what we need to do, we have created a Web application and hosted it IIS where msvsmon is running, We need to connect it from our local system where we are having our code. Now lets have a look in the case of windows authentication mode
First of all we need to open the application from visual studio in our development system. Now we need to attach the process from remote server. Goto
Fig: Attach Process From Visual Studio
When we will click on the "
Attach to Process" we will get the following screen .
Fig: Default Process ListRight now it is showing all the process that are currently running on the system. Now we need to connect it the remote system. Now I have already started a msvsmon with name
"abhijit.jana"and it is waiting for a new connection.
Fig: msvsmon is running on remote host
Now, I am going to connect with the remote system from my local visual studio IDE. So, what we need to do. We have to give the remote server name to the Qualifier section in attach process window.
Fig: Connect with Remote host and get the list of process
Now, in the process list all the process are listed from remote server along with Worker Process (
(w3wp.exe). Now this is the exact worker process which we need to attach with our code. One more thing, when we are getting the list of process from it means remote server is connected. Now if we check the msvsmon window, it will show another message that user is connected. Have a look into the screenshot
Fig: Debug monitor showing message of connectionNow, our application is ready to debug. just set a break point in your code and enjoy the debugging. Here is our web site [
Hosted on Remote IIS Server] and which having a server side button, and I want to debug the application on the click of button.
Fig: Access site from Host URLNow process is attached in our visual studio and I have set the breakpoint on the button click method. Here is outcome.
Fig: Debugger at breakpointSo, let enjoy the debugging from remote server . Now lets have a look how will we remote debug in
"16">Process Attach - No Authentication Mode
This is quite similar to windows authentication process attach. I have already discussed that, how to configure the No-Authentication mode in remote debugger. We have to attach the process similar way that I have discussed. There are some few changes. Transport mode should be selected to -
Remote (Native only with no authentication)[ Check the Screen shots] .And we need to provide the qualifier "
". Have a look into screen shots,
Fig: Process Attach for No-Authentication ModeSo, now we need to attach the worker process and need to start debugging, on which I have already discussed. There is slight change in connect while remote debugging going on with No-Authentication mode. Debugging monitor will display a message on the window that debugging is running on no authentication mode.
Fig: Status message for No-Authentication ModeSo, this is all about how to debug you application from remote IIS server in both windows and No-Authentication mode.
This is one of the most fantastic features of Msvsmon tool. Msvsmon debugging monitor tool allow multiple user to debug simultaneously. . Each instance of the remote debugger has a
unique server name. As I have already shown that Server names are configurable, so we can give an instance of the remote debugger any server name. Now multiple user can able to access the same
Fig: General block diagram from Multiple Debugger instance
- Visual Studio 2005 remote debugging components must be installed on the remote computer
- we must reference the remote computer by using a computer name instead of an IP address.
- The Web.config file for the ASP.NET application must not contain any errors, and the compilation element must have the debug attribute set to True.
- Make sure that a firewall is not blocking remote debugging.
- The security setting for the site must allow Integrated Windows authentication.
- Make sure that the Remote Debugging Monitor is running on the remote server. If Msvsmon.exe is not running, then you will receive the error message.
Fig: Overall Summary
Hope this article will help you to learn about remote debugging.