<s>
Prior	O
to	O
IIS	B-Application
7	I-Application
,	O
Microsoft	O
's	O
Internet	B-Application
Information	I-Application
Services	I-Application
stores	O
its	O
information	O
in	O
an	O
internal	O
database	O
called	O
the	O
MetaBase	O
.	O
</s>
<s>
The	O
metabase	O
is	O
an	O
inheritable	O
,	O
hierarchical	O
database	O
that	O
allows	O
for	O
configuration	O
of	O
HTTP/HTTPS	O
,	O
FTP	B-Protocol
,	O
SMTP	B-Protocol
,	O
and	O
NNTP	B-Protocol
at	O
the	O
server	O
,	O
the	O
site	O
,	O
or	O
the	O
folder	O
or	O
file	O
level	O
.	O
</s>
<s>
Different	O
versions	O
of	O
IIS	O
use	O
different	O
formats	O
;	O
prior	O
to	O
IIS	O
version	O
6	O
this	O
was	O
always	O
a	O
proprietary	O
format	O
,	O
whereas	O
with	O
6.0	O
and	O
later	O
the	O
data	O
is	O
stored	O
in	O
XML	B-Protocol
files	O
.	O
</s>
<s>
The	O
metabase	O
consists	O
of	O
two	O
files	O
,	O
MetaBase.xml	O
and	O
MBSchema.xml	O
,	O
stored	O
in	O
the	O
%SystemRoot%	O
\system32\inetsrv\	O
directory	O
.	O
</s>
<s>
Changes	O
to	O
the	O
IIS	O
configuration	O
via	O
the	O
IIS	O
Manager	O
or	O
programmatic	O
changes	O
get	O
written	O
to	O
the	O
in-memory	O
metabase	O
,	O
then	O
are	O
persisted	O
to	O
the	O
on-disk	O
MetaBase.xml	O
file	O
after	O
a	O
number	O
of	O
changes	O
.	O
</s>
<s>
Internet	B-Application
Information	I-Application
Services	I-Application
 '	O
central	O
metabase	O
is	O
eliminated	O
in	O
IIS	O
version	O
7	O
in	O
favor	O
of	O
a	O
set	O
of	O
XML	B-Protocol
configuration	O
files	O
that	O
are	O
located	O
centrally	O
in	O
the	O
Machine.config	O
and	O
ApplicationHost.config	O
files	O
and	O
within	O
the	O
web	O
site	O
's	O
infrastructure	O
using	O
web.config	O
files	O
.	O
</s>
<s>
The	O
IIS	O
Manager	O
interface	O
,	O
an	O
MMC-based	O
administration	O
console	O
,	O
is	O
the	O
primary	O
means	O
of	O
modifying	O
the	O
Metabase	O
.	O
</s>
<s>
The	O
XML	B-Protocol
files	O
are	O
human-readable	O
,	O
and	O
when	O
the	O
Allow	O
direct	O
metabase	O
edits	O
feature	O
is	O
turned	O
on	O
(	O
not	O
recommended	O
by	O
Microsoft	O
)	O
it	O
can	O
be	O
viewed	O
and	O
edited	O
with	O
simple	O
text	O
editing	O
software	O
like	O
Notepad	B-Application
.	O
</s>
<s>
The	O
Metabase	O
is	O
also	O
programmable	O
through	O
several	O
APIs	O
-	O
Admin	O
Base	O
Objects	O
(	O
ABO	O
)	O
,	O
Active	B-Protocol
Directory	I-Protocol
Services	I-Protocol
Interface	I-Protocol
(	O
ADSI	O
)	O
,	O
Windows	B-Library
Management	I-Library
Instrumentation	I-Library
(	O
WMI	O
)	O
,	O
and	O
the	O
.NET	B-Application
Framework	I-Application
's	O
System.DirectoryServices	O
and	O
Microsoft.Web.Administration	O
.	O
</s>
