Linux System Administration

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Chapter 6: Administering Apache

The alias (new name) comes first in the directive, followed by the actual location of

the directory. The directory may be outside of the document root. In this case, the

file /tmp/test/button.gif would be accessible as the URL http://www.example.com/test/

button.gif, even though it’s not in /var/www/test.

Limits

On a busy server, Apache can create many simultaneous child processes and use a lot

of memory. This can increase the load average and make the system sluggish or even

unresponsive. Table 6-2 shows how you can limit some of Apache’s runtime values

in the site configuration file.

Server-Side Includes

SSI can be used to include file contents, the output of programs, or the contents of

environment variables as part of an HTML file. The syntax to specify SSI in Apache

configuration files can be misleading. For example, to allow only server-side includes

in /var/www/ssi but no other options, create the directory:

# mkdir /var/www/ssi

and tell Apache to allow only SSI within it:

<Location /ssi>

Options Includes

</Location>

To add SSI to existing options, use:

<Location /ssi>

Options +Includes

</Location>

SSI lets you include file contents, but it can also run any program and include its out-

put. This can be unsafe, so to restrict SSI inclusion to file contents only, use:

Table 6-2. Apache resource directives

Directive Default Usage

MaxClients 256

Maximum simultaneous ...