Metabase

Microsoft's Internet Information Services stores its information in an internal database called the MetaBase. The metabase is an inheritable, hierarchical database that allows for configuration of HTTP/HTTPS, FTP, SMTP, and NNTP at the server, the site, or the folder or file level. Different versions of IIS use different formats; prior to IIS version 6 this was always a proprietary format, whereas with 6.0 and later the data is stored in XML files. The metabase consists of two files, MetaBase.xml and MBSchema.xml, stored in the %SystemRoot%system32inetsrv directory. The metabase periodically gets backed up to the MetaBack subdirectory.

When Internet Information Service starts, it reads the two metabase files to create an in-memory cache of the web server's configuration, which is referred to as the "in-memory metabase". [cite book |author=The Microsoft IIS Team |title=Internet Information Services (IIS) 6.0 Resource Kit |publisher=Microsoft Press |location=Redmond, Wash |year=2004 |pages=513-564 |isbn=0-7356-1420-2] Changes to the IIS configuration via the IIS Manager or programmatic changes get written to the in-memory metabase, then are persisted to the on-disk MetaBase.xml file after a number of changes. [cite web
url = http://technet2.microsoft.com/windowsserver/en/library/fb8964b7-d595-4ad0-821d-e00e269774741033.mspx
title = Overview of the IIS 6.0 Metabase |accessdate = 2007-09-10 |date=2005-08-22 |publisher=Microsoft Corporation]

Internet Information Services' central metabase is eliminated in IIS version 7 in favor of a set of XML configuration files that are located centrally in the Machine.config and ApplicationHost.config files and within the web site's infrastructure using web.config files. This allows for easy synchronization of web sites across servers by including all configuration information within the web site's root directory.

Metabase administration

The IIS Manager interface, an MMC-based administration console, is the primary means of modifying the Metabase. IIS also optionally provides a web-based administration console. The XML files are human-readable, and when the "Allow direct metabase edits" feature is turned on (not recommended by Microsoft [cite web |url=http://technet.microsoft.com/en-us/library/aa997548.aspx |title=How to Enable the Enable Direct Metabase Edit Feature in IIS Manager |publisher=Microsoft Corporation |date=2005-05-23 |accessdate=2007-09-10] ) it can be viewed and edited with simple text editing software like Notepad.

The Metabase is also programmable through several APIs - Admin Base Objects (ABO), Active Directory Services Interface (ADSI), Windows Management Instrumentation (WMI), and the .NET Framework's System.Directory Services.

References

External links

* [http://www.microsoft.com/iis Microsoft Internet Information Services product page]
* [http://search.iis.net/search/iis/techcenter/Metabase%20Configuration Metabase Configuration] - IIS.net