In-depth analysis of IIS 6.0 (13)

IIS wildcard applications can do anything developers need to do, such as URL customization, authentication, recording of special log information, detection of attack attempts, creation of content, and so on. After the wildcard application finishes processing, it forwards the request to the appropriate processing engine (for example, processing the asp.dll of the ASP page), and the processing engine further processes the request. In addition, wildcard applications can pass requests to any page in the same application pool by invoking the Executeurl feature that is added to the ISAPI application.

The new ISAPI wildcard application opens the door to creative application design. For example, the URL authorization feature of IIS 6.0 is implemented as an ISAPI wildcard application (URLAuth.dll). The URL authorization feature allows IIS 6.0 to grant access to a URL based on a series of rules, such as whether a user is a member of a group, a geographic location, and other information about the user in a database or AD. For more information about ISAPI wildcard applications and URL authorization, see the Help documentation for IIS 6.0.

Five, log function

The logging capabilities of the server are rarely the primary concern, but they are an indispensable adjunct to server management and monitoring work day in and day out. IIS 6.0 has a number of significant improvements in logging functionality, but unfortunately, W3SVC log events still cannot be logged in local time.

In IIS 6.0, the logging functionality has been changed to http.sys implementation, and HTTP.sys is running in kernel mode. This improvement accelerates log write speed while avoiding multiple worker processes competing for the same log file. In some special cases, HTTP.sys encounters an error, and it should but cannot write log information to the Web site's log, for example, the worker process is being reclaimed, the HTTP.sys is prevented from processing the user's request, or the user is trying to connect to the server, but only part of the information required for IIS is provided in the If such a situation occurs, HTTP.sys writes the event to a new log file Httperr.log.

Httperr.log log files are important in troubleshooting and optimizing IIS 6.0. By default, the Httperr.log file is saved in the \System32\LogFiles directory, but can be modified, and the method is found hkey_local_machine\system\currentcontrolset\services\ Http\parameters register the subkey, add a string value named Errorloggingdir below it, and set the full path to save the log file in Errorloggingdir. The information that can be found in the Httperr.log log file includes all 503 (Service Unavailable) errors, idle connection timeout, various errors that occur when parsing URLs, and the last 10 requests submitted to the failed application pool.

IIS 6.0 also has a feature called binary logging that, when enabled, IIS 6.0 writes all the log information for a Web site to a binary-formatted log file with the name extension. ibl. To enable binary logging, simply set the w3svcc/centralbinaryloggingenabled entry of the configuration file to Ture (1). This feature should be useful for ISPs. There may be 1000 or more Web sites on each ISP's machine, and if each Web site generates a log file every day, the total number of log files will soon reach an astronomical figure. Microsoft's recently released Log Parser 2.0 tool is able to read binary log files and generate reports that can be made from http://download.microsoft.com/download/iis50/utility/2.0/nt5xp/ En-us/setup.exe download. Log Parser 2.0 can also read the Httperr.log file described earlier and generate a report.

From a long time ago, IIS allows you to specify the directory where the log files are saved on the local server. However, although IIS 5.0 and IIS 4.0 IIS Manager allow you to enter a universal naming convention (UNC) path for a remote server when specifying the log file path, the Web server does not actually save the log to a remote server. Only IIS 6.0 will actually support the UNC pathname of the log file path