IIS 7

What is break mode? What are the options to step through code?
Answer - Break mode lets you to observe code line to line in order to locate error.
VS.NET provides following option to step through code.
Step Into
Step Over
Step Out
Run To Cursor
Set Next Statement

Debug Vs Trace.
Answer - Both these objects are found in the System.Diagnostics namespace.
Both are used for diagnose problems without interrupting application execution.
Debug statement can only be used in debug mode while trace statement can be used both in debug and released mode.
Debug statements can't be compiled into a release version.

Define trace class.
Answer - The trace class in the code is used to diagnose problem.
You can use trace messages to your project to monitor events in the released version of the application.
The trace class is found in the System.Diagnostics namespace.

Define Trace Switches.
Answer - Trace switches are used to configure tracing behavior.
There are two kinds of trace switches: BooleanSwitch and TraceSwitch.
BooleanSwitch: It is either on or off.
TraceSwitch : It has property to determine trace behaviour.
Trace switches can be configured through application's .config file even after the application is compiled.

what is debugging.
debugging is an error correction because 'bug' means error
correct and 'de' including that is determinate the errors
and correct them


IIS Versions 1.0 to 4.0
IIS was released with Service Pack 3 for Windows NT 3.51, as a set of services providing HTTP, Gopher, and WAIS functionality. Although the functions were there, most users chose alternates from third-party vendors such as O'Reilly's Website or Netscape's server. Although these services had been available for years with the various flavors of UNIX operating systems, native Internet services for Windows were mostly an afterthought, with little integration with the Windows operating system.

With the advent of Windows NT 4.0, IIS also matured in version 2.0. The most notable improvement in IIS version 2.0 was closer integration with the Windows NT operating system, taking advantage of Windows security accounts and providing integrated administration through a management console similar to many other Windows services. IIS 2.0 introduced support for HTTP Host headers, which allowed multiple sites to run on a single IP address, and aligned Microsoft's IIS development with NCSA standards, providing for NCSA common log formats and NCSA-style map files. IIS 2.0 also intro-duced a web browser interface for management, and content indexing through Microsoft's Index Server.

IIS version 3.0 was introduced with Windows NT Service Pack 3 and introduced the world to ASP (Active Server Pages) and Microsoft's concept of an application server. A precursor to the ASP.NET envi-ronment, ASP (now referred to as classic ASP) is a server-side scripting environment for the creation of dynamic web pages. Using VBScript, JScript or any other active scripting engine, programmers finally had a viable competitor to CGI and scripting technologies available on non-Microsoft platforms, such as Perl.

IIS 4.0, available in the NT Option Pack, introduced ASP 2.0, an object-based version of ASP that included six built-in objects to provide standardized functionality in ASP pages. IIS 4.0 was the last version of IIS that could be downloaded and installed outside of the operating system.

IIS 5.0 and 5.1
With the release of Windows 2000, IIS became integrated with the operating system. Version numbers reflected the operating system, and there were no upgrades to IIS available without upgrading the oper-ating system. IIS 5.0 shipped with Windows 2000 Server versions and Windows 2000 Professional, and IIS version 5.1 shipped with Windows XP Professional, but not Windows XP Home Edition. For all essential functions, IIS 5.0 and IIS 5.1 are identical, differing only slightly as needed by the changes to the operating system.

With Windows 2000 and IIS 5.0, IIS became a service of the operating system, meant to be the base for other applications, especially for ASP applications. The IIS 5.0 architecture served static content, ISAPI functions, or ASP scripts, with ASP script processing handed off to a script engine based on the file extension. Using file extensions to determine the program that handles the file has always been a com-mon part of Windows functionality, and in the case of ASP processing, the speed of serving pages was increased by the automatic handoff of ASP scripts directly to the ASP engine, bypassing the static con-tent handler. This architecture has endured in IIS to the current version.

IIS 6.0
IIS 6.0 shipped with Windows Server 2003 editions and Windows XP Professional 64bit edition, which was built on the Windows Server 2003 Service Pack 1 code base. IIS 6.0 was identical among operating system versions, but there were restrictions or expansions depending on the version of Server 2003 under which IIS was running. For example, Server 2003 Web Edition would only run IIS and a few ancil-lary services; it could not be used to run Microsoft SQL Server. On the other end of the spectrum, only the Enterprise and Data Center versions of Server 2003 included clustering technology.

Operating system changes also expanded the capabilities of IIS as an application server. Native XML Web Services appeared in Server 2003. Process-independent session states made web farms easier to configure and manage, allowing session states to be stored outside the application for redundancy and failover. Web farms also became easier with Server 2003's improved Network Load-Balancing features, such as the NLB Manager, which provided a single management point for NLB functions.

IIS 7.0 Versions
Although there is really only a single version of IIS 7.0, the availability and capabilities vary with the choice of operating system. Because IIS 7.0 is tied to the operating system, as were all versions of IIS since IIS 4.0, it is not available on operating systems prior to Vista or Windows Server 2008. As in Windows XP, the workstation operating systems have limited IIS functionality or no functionality at all. Unlike in Windows XP, Vista versions have no concurrent HTTP connection limitations but instead use concurrent request processing limitations. In XP, reaching a maximum concurrent HTTP connection limit would result in IIS returning a 403.9 result code (too many users), while a request limitation merely queues requests in the order received. The end result is slower response, but no errors.

Some Windows Server 2008 versions also have limitations that affect IIS 7.0. Although IIS 7.0 is included with no limitations in all server versions, the server version itself may have limitations in use. For exam-ple, if you install Windows Server 2008 Core Edition, IIS 7.0 can be installed, but there is no GUI configu-ration application. This version of Windows does not have the .NET Framework available; thus, no managed code can be run on the server.

Windows Server 2008 Web Edition has no functional limits to IIS, but only supports three role services: Web Server, Windows Media Server and Sharepoint Services — it cannot be used to host a Domain Controller, or other types of roles. The following table shows which versions of Windows Vista and Windows Server 2008 have IIS 7.0 and what the limitations are.

IIS 7.0 Features
1)Integrated request pipeline
2) Configurability
3)Extensible Configuration Schemas
4) Componentization (Security,Minimal Installation,Management Delegation,Unified Authentication and Authorization,Request Filtering,Remote Management)
5)Administration Tools
6)AppCmd.exe Command-Line Utility
7)Diagnostics

IIS 7.0 is a ground-up rewrite of IIS 6.0, designed as an integrated web application platform. Integration with the ASP.NET framework combined with fully exposed APIs for complete extensibility of the plat-form and management interfaces make IIS 7.0 a programmer's dream. Security that includes delegation of configuration and a complete diagnostic suite with request tracing and advanced logging satisfies the administrator's desires.

While the most substantial change in IIS 7.0 may be the integration of ASP.NET into the request pipeline, the extensibility of IIS 7.0, configuration delegation and the use of XML configuration files, request trac-ing and diagnostics, and the new administration tools are all welcome changes from previous versions of IIS.

Unlike previous versions of IIS, the modular design of IIS 7.0 allows for easy implementation of custom modules and additional functionality. This increased functionality can come from in-house development, third-party sources, or even Microsoft. Since these modules and additional programs can be plugged into IIS at any time, without changing core operating system functions, the Microsoft IIS devel-opment team can ship additional supported and unsupported modules outside of Microsoft's standard service pack process. The bottom line is that you get what you need faster. Microsoft's web site at http://www.iis.net is the source for these additional downloads.

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IIS 7.0 is an evolution of previous IIS versions, building on their strengths while overcoming their weak-nesses. Microsoft has listened to user comments on previous versions and responded positively, to make IIS 7.0 the most robust, configurable, and secure version of their web server. In addition, Microsoft has further enhanced the tie between IIS and ASP.NET, making IIS 7.0 a fully functional application server with entirely integrated processing and configuration of both sides.

Programmers will see the improvements in IIS 7.0 as making their job easier and more manageable. They will no longer need to justify web server changes that might affect numerous sites just to adapt to their application. True XCopy deployment of applications and configurations will allow them to spend less time on deployment schemes that need to work around server configurations. Senior programmers on a site will be able to delegate appropriate permissions for configuration changes to junior programmers, just as administrators will delegate permission to developers.

Administrators will find that the delegation in IIS 7.0 greatly assists in lowering the administrative effort required to maintain an IIS server. Administrators will be able to granularly control their servers and site administration functions while allowing developers to control the areas they need to. Security concerns about opening servers to development staff are a thing of the past, and auditors will be pleased with the control available. The reduction in security exposure provided by the modular installation, as well as the ability to provide unified authentication across an entire site, will further help to lock down an already secure system. Administrators will also enjoy the simplified and unified management tools.

Both administrators and developers will appreciate IIS 7.0's tracing and diagnostic capabilities. The abil-ity to see into a request will ease troubleshooting failed requests as well as allow better tuning for per-formance even in completed requests. The modularity of IIS will also appeal to both camps, especially the ability to write custom modules that sit in the request pipeline and affect all requests, whether for a custom authentication system or simply to add a copyright notice to all images or content served.

After reviewing this chapter, you should have a good idea of the changes and new features in IIS 7.0. The following chapters will take you through installing and configuring the web server and environ-ment. If you have a particular interest, feel free to skip to the chapter or chapters covering it. Otherwise, let's take an in-depth look at the architecture of IIS 7.0, followed by planning your installation and installing IIS 7.0.

INETINFO.EXE,ISAPI.EXE,WP.EXE

inetinfo.exe is the Microsoft IIS server running, handling ASP.NET requests among other things. When an ASP.NET request is received (usually a file with .aspx extension), the ISAPI filter aspnet_isapi.dll takes care of it by passing the request to the actual worker process aspnet_wp.exe


When a request comes into Microsoft's IIS Web server (inetinfo.exe, is ur webserver running) its extension is examined and, based on this extension, the request is either handled directly by IIS or routed to an ISAPI extension. An ISAPI extension is a compiled class that is installed on the Web server and whose responsibility it is to return the markup for the requested file type.

By default, IIS handles the request, and simply returns the contents of the file requested. This makes sense for static files, like images, HTML pages, CSS files, external JavaScript files, and so on. For example, when a request is made for a .html file, IIS simply returns the contents of the requested HTML file.

For files whose content is dynamically generated, the ISAPI extension configured for the file extension is responsible for generating the content for the requested file. For example, a Web site that serves up classic ASP pages has the .asp extension mapped to the asp.dll ISAPI extension. The asp.dll ISAPI extension executes the requested ASP page and returns its generated HTML markup. If your Web site serves up ASP.NET Web pages, IIS has mapped the .aspx to aspnet_isapi.dll, an ISAPI extension that starts off the process of generating the rendered HTML for the requested ASP.NET Web page.

The aspnet_isapi.dll ISAPI extension is a piece of unmanaged code. That is, it is not code that runs in the .NET Framework. When IIS routes the request to the aspnet_isapi.dll ISAPI extension, the ISAPI extension routes the request onto the ASP.NET engine(aspnet_wp.exe), which is written in managed code - managed code is code that runs in the .NET Framework.

Diifference of IIS 6 and IIS 7
Architecture Monolithic Modular
Setup Most Features Installed Minimum installtion based on role
Extended Features ISAPI Filter and ISAPI Extention Added Module&handler managed code
Customize UI Normal Customize for .NET

IIS 7 Authentication:Each application pool is configured to run under the content of a user account and the default value for this account is NETWORKSERVICE.

IIS7 IP Restriction:allowUnlisted". This property was added to make it easier to configure security policies for your system at a global level.