IIS_Metabase
IIS Metabase
Microsoft Metabase
Prior to IIS 7, 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%\system32\inetsrv\
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.[1] 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.[2]
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 synchronization of web sites across servers by including all configuration information within the web site's root directory.