The Subnet command is another way to
describe the Web area for indexing. It works almost
like Server command but takes a string with wildcards as its
pattern argument which is compared against
the IP address instead of the URL.
Pattern can have
? and * signs
meaning one character and
any number of characters respectively.
The MatchType optional parameter
can be either Match or NoMatch,
with the former as default. When MatchType
is set to NoMatch, the meaning of the command changes
inside out: index documents which don't belong
to the given Subnet.