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Overview
The
<system.webServer>
element specifies the root element for many of the site-level and application-level configuration settings for Internet Information Services (IIS) 7 in the ApplicationHost.config file, and contains configuration elements that define the settings used by the Web server engine and modules.
Unlike settings that are found in <
system.applicationHost
>, settings in the
<system.webServer>
element can be delegated.
Compatibility
Version
Notes
IIS 8.0
The
<applicationInitialization>
and
<webSocket>
elements were added as child elements.
IIS 7.5
The
<system.webServer>
element was not modified in IIS 7.5.
IIS 7.0
The
<system.webServer>
element was introduced in IIS 7.0.
IIS 6.0
How To
There are no examples that are specific to the
<system.webServer>
element. For examples that configure the settings that are found within the
<system.webServer>
element, see the child elements that are listed in the
configuration details
section of this topic.
Configuration
The
<system.webServer>
element is defined in the ApplicationHost.config file, although settings in
<system.webServer>
element can be delegated to Web.config files.
Attributes
None.
Child Elements
Element
Description
applicationInitialization
Optional element.
Configures settings for application initialization that is performed proactively before a request is received.
Optional element.
Configures settings for Active Server Pages (ASP) applications.
caching
Optional element.
Configures output cache settings.
Optional element.
Configures default settings for Common Gateway Interface (CGI) applications.
defaultDocument
Optional element.
Configures settings for returning a default document to a client browser when the client does not specify a file name in a request.
directoryBrowse
Optional element.
Configures whether directory browsing is enabled or disabled on the Web server, and specifies the information to include in a directory listing.
fastCgi
Optional element.
Contains a collection of fastCgi application pool definitions.
globalModules
Optional element.
Specifies configuration settings for global modules on a Web server.
handlers
Optional element.
Specifies handlers to process requests made to sites and applications.
httpCompression
Optional element.
Configures HTTP compression settings for a Web server.
httpErrors
Optional element.
Configures HTTP error messages for a Web server.
httpLogging
Optional element.
Specifies configuration settings for HTTP.sys logging.
httpProtocol
Optional element.
Configures custom and redirect response headers to be sent from the server to the client.
httpRedirect
Optional element.
Configures settings for redirecting client requests to a new location.
httpTracing
Optional element.
Specifies configuration settings for HTTP.sys tracing.
isapiFilters
Optional element.
Specifies configuration settings for ISAPI filters on a Web server.
management
Optional element.
Configures a Web server for remote management by using IIS Manager.
modules
Optional element.
Specifies configuration settings for modules on a Web server.
odbcLogging
Optional element.
Configures Open Database Connectivity (ODBC) logging.
security
Optional element.
Specifies the section group that contains security-related sections.
serverRuntime
Optional element.
Configures request limits for applications on a Web server.
serverSideInclude
Optional element.
Specifies whether server-side includes (SSI) #exec directives are disabled.
staticContent
Optional element.
Configures static file request handler settings.
tracing
Optional element.
Configures request trace settings.
urlCompression
Optional element.
Configures compression of static and dynamic content.
validation
Optional element.
Configures IIS 7 to detect whether an ASP.NET application that is set up to run in ISAPI mode needs any migration in order to function correctly in Integrated mode.
webdav
Optional element.
Configures WebDAV publishing settings.
webSocket
Optional element.
Configures communications over the WebSocket protocol.
Configuration Sample
The following configuration sample defines a simple, static-content-only
<system.webServer>
element.
<system.webServer>
<asp />
<caching enabled="true" enableKernelCache="true" />
<cgi />
<defaultDocument enabled="true">
<files>
<add value="Default.htm" />
<add value="Index.htm" />
<add value="Index.html" />
</files>
</defaultDocument>
<directoryBrowse enabled="false" />
<fastCgi />
<globalModules>
<add name="UriCacheModule" image="%windir%\System32\inetsrv\cachuri.dll" />
<add name="FileCacheModule" image="%windir%\System32\inetsrv\cachfile.dll" />
<add name="TokenCacheModule" image="%windir%\System32\inetsrv\cachtokn.dll" />
<add name="HttpCacheModule" image="%windir%\System32\inetsrv\cachhttp.dll" />
<add name="StaticCompressionModule" image="%windir%\System32\inetsrv\compstat.dll" />
<add name="DefaultDocumentModule" image="%windir%\System32\inetsrv\defdoc.dll" />
<add name="DirectoryListingModule" image="%windir%\System32\inetsrv\dirlist.dll" />
<add name="ProtocolSupportModule" image="%windir%\System32\inetsrv\protsup.dll" />
<add name="StaticFileModule" image="%windir%\System32\inetsrv\static.dll" />
<add name="AnonymousAuthenticationModule" image="%windir%\System32\inetsrv\authanon.dll" />
<add name="RequestFilteringModule" image="%windir%\System32\inetsrv\modrqflt.dll" />
<add name="CustomErrorModule" image="%windir%\System32\inetsrv\custerr.dll" />
<add name="HttpLoggingModule" image="%windir%\System32\inetsrv\loghttp.dll" />
<add name="RequestMonitorModule" image="%windir%\System32\inetsrv\iisreqs.dll" />
</globalModules>
<httpCompression directory="%SystemDrive%\inetpub\temp\IIS Temporary Compressed Files">
<scheme name="gzip" dll="%Windir%\system32\inetsrv\gzip.dll" />
<staticTypes>
<add mimeType="text/*" enabled="true" />
<add mimeType="message/*" enabled="true" />
<add mimeType="application/javascript" enabled="true" />
<add mimeType="*/*" enabled="false" />
</staticTypes>
</httpCompression>
<httpErrors>
<error statusCode="401" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="401.htm" />
<error statusCode="403" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="403.htm" />
<error statusCode="404" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="404.htm" />
<error statusCode="405" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="405.htm" />
<error statusCode="406" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="406.htm" />
<error statusCode="412" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="412.htm" />
<error statusCode="500" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="500.htm" />
<error statusCode="501" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="501.htm" />
<error statusCode="502" prefixLanguageFilePath="%SystemDrive%\inetpub\custerr" path="502.htm" />
</httpErrors>
<httpLogging dontLog="false" />
<httpProtocol />
<httpRedirect />
<httpTracing />
<isapiFilters />
<odbcLogging />
<security>
<access sslFlags="None" />
<applicationDependencies />
<authentication>
<anonymousAuthentication enabled="true" userName="IUSR" />
<basicAuthentication />
<clientCertificateMappingAuthentication />
<digestAuthentication />
<iisClientCertificateMappingAuthentication />
<windowsAuthentication />
</authentication>
<authorization />
<ipSecurity />
<isapiCgiRestriction notListedIsapisAllowed="false" notListedCgisAllowed="false">
<clear />
</isapiCgiRestriction>
<requestFiltering>
<fileExtensions allowUnlisted="true" applyToWebDAV="true" />
<verbs allowUnlisted="true" applyToWebDAV="true" />
<hiddenSegments applyToWebDAV="true">
<add segment="Web.config" />
</hiddenSegments>
</requestFiltering>
</security>
<serverRuntime />
<serverSideInclude />
<staticContent lockAttributes="isDocFooterFileName">
<mimeMap fileExtension=".png" mimeType="image/gif" />
<mimeMap fileExtension=".htm" mimeType="text/html" />
<mimeMap fileExtension=".html" mimeType="text/html" />
<mimeMap fileExtension=".jpeg" mimeType="image/jpeg" />
<mimeMap fileExtension=".png" mimeType="image/jpeg" />
<mimeMap fileExtension=".js" mimeType="application/x-javascript" />
<mimeMap fileExtension=".png" mimeType="image/png" />
<mimeMap fileExtension=".txt" mimeType="text/plain" />
</staticContent>
<tracing>
<traceFailedRequests />
<traceProviderDefinitions />
</tracing>
<urlCompression />
<validation />
<webSocket />
</system.webServer>
Sample Code
There are no code samples that are specific to the <system.webServer>
element. For code samples that configure the settings that are found within the <system.webServer>
element, see the child elements that are listed in the configuration details section of this topic.