Sun Microsystems Netscape Enterprise Server, Руководство администратора

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Chapter 7, Configuring Server Preferences 175
Working with Dynamic Configuration Files
Using .nsconfig Files
With
.nsconfig
files, you can allow end users to apply access control or
customize error messages without allowing them to use CGI or parsed HTML.
The format and capability of these dynamic configuration files is described in
“Writing .nsconfig Files” on page 176
.
When a request is made for a resource in which dynamic configuration is
enabled, the server must search for the configuration files within one or more
directories of that resource. This search can be an expensive operation in terms
of performance, so the server lets you configure how much flexibility you need,
weighing it against the efficiency cost.
You can provide a base directory to the server, in which case the server starts
its search for configuration files from the filesystem directory. Alternatively, you
can provide no base directory, in which case the server attempts to infer the
base directory from the URL. That is, if the requested URL is to a file in the
document root, the server starts searching from the document root.
You also specify the name of the configuration file to search for within the base
directory.
If you centralize all of your configuration information for the subdirectories of
the base directory in the base directory’s configuration file, the server is more
efficient because it doesn’t have to search for configuration files in the
subdirectories.
However, you may sometimes want the server to search the subdirectories. If
you do, the server searches for
.nsconfig
files starting from the top level
directory and searching downward until reaching the directory in which the
referenced resource resides. The server processes
.nsconfig
files in the order
it encounters them. If a top level file restricts a user’s access, the server does
not give the user access, even though a lower level file might allow access.
The server processes all restrictions based on IP address and DNS entry
(
RestrictAccess
directive) as it finds them in a file. If the server finds a file
that denies a user access because of IP address or DNS entry, it stops
processing files. The server collects restrictions based on user name
(
RequireAuth
directive) and processes them at the end, unless the request
has already been denied because of IP address or DNS entry.