rse 00/02/10 08:35:50
Modified: htdocs/manual/misc rewriteguide.html
Log:
Cleanup my old physical HTML markup into a logical one to
fit better into the Apache documentation.
Revision Changes Path
1.3 +179 -179 apache-1.3/htdocs/manual/misc/rewriteguide.html
Index: rewriteguide.html
===================================================================
RCS file: /home/cvs/apache-1.3/htdocs/manual/misc/rewriteguide.html,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -r1.2 -r1.3
--- rewriteguide.html 2000/02/10 16:24:26 1.2
+++ rewriteguide.html 2000/02/10 16:35:48 1.3
@@ -28,14 +28,14 @@
</DIV>
<P>
-This document supplements the mod_rewrite <a
-href="../mod/mod_rewrite.html">reference documentation</a>. It describes
+This document supplements the mod_rewrite <A
+HREF="../mod/mod_rewrite.html">reference documentation</a>. It describes
how one can use Apache's mod_rewrite to solve typical URL-based problems
webmasters are usually confronted with in practice. I give detailed
descriptions on how to solve each problem by configuring URL rewriting
rulesets.
-<H2><a name="ToC1">Introduction to mod_rewrite</a></H2>
+<H2><A name="ToC1">Introduction to mod_rewrite</a></H2>
The Apache module mod_rewrite is a killer one, i.e. it is a really
sophisticated module which provides a powerful way to do URL manipulations.
@@ -50,7 +50,7 @@
of its power. This paper tries to give you a few initial success events to
avoid the first case by presenting already invented solutions to you.
-<H2><a name="ToC2">Practical Solutions</a></H2>
+<H2><A name="ToC2">Practical Solutions</a></H2>
Here come a lot of practical solutions I've either invented myself or
collected from other peoples solutions in the past. Feel free to learn the
@@ -60,7 +60,7 @@
ATTENTION: Depending on your server-configuration it can be necessary to
slightly change the examples for your situation, e.g. adding the [PT] flag
when additionally using mod_alias and mod_userdir, etc. Or rewriting a
ruleset
-to fit in <tt>.htaccess</tt> context instead of per-server context. Always
try
+to fit in <CODE>.htaccess</CODE> context instead of per-server context.
Always try
to understand what a particular ruleset really does before you use it. It
avoid problems.
@@ -83,12 +83,12 @@
<DD>
We do an external HTTP redirect for all non-canonical URLs to fix them in the
location view of the Browser and for all subsequent requests. In the example
-ruleset below we replace <tt>/~user</tt> by the canonical <tt>/u/user</tt>
and
-fix a missing trailing slash for <tt>/u/user</tt>.
+ruleset below we replace <CODE>/~user</CODE> by the canonical
<CODE>/u/user</CODE> and
+fix a missing trailing slash for <CODE>/u/user</CODE>.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteRule ^/<b>~</b>([^/]+)/?(.*) /<b>u</b>/$1/$2 [<b>R</b>]
-RewriteRule ^/([uge])/(<b>[^/]+</b>)$ /$1/$2<b>/</b> [<b>R</b>]
+RewriteRule ^/<STRONG>~</STRONG>([^/]+)/?(.*) /<STRONG>u</STRONG>/$1/$2
[<STRONG>R</STRONG>]
+RewriteRule ^/([uge])/(<STRONG>[^/]+</STRONG>)$ /$1/$2<STRONG>/</STRONG>
[<STRONG>R</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -126,26 +126,26 @@
<DT><STRONG>Description:</STRONG>
<DD>
Usually the DocumentRoot of the webserver directly relates to the URL
-``<tt>/</tt>''. But often this data is not really of top-level priority, it
is
+``<CODE>/</CODE>''. But often this data is not really of top-level priority,
it is
perhaps just one entity of a lot of data pools. For instance at our Intranet
-sites there are <tt>/e/www/</tt> (the homepage for WWW), <tt>/e/sww/</tt>
(the
+sites there are <CODE>/e/www/</CODE> (the homepage for WWW),
<CODE>/e/sww/</CODE> (the
homepage for the Intranet) etc. Now because the data of the DocumentRoot
stays
-at <tt>/e/www/</tt> we had to make sure that all inlined images and other
+at <CODE>/e/www/</CODE> we had to make sure that all inlined images and other
stuff inside this data pool work for subsequent requests.
<P>
<DT><STRONG>Solution:</STRONG>
<DD>
-We just redirect the URL <tt>/</tt> to <tt>/e/www/</tt>. While is seems
+We just redirect the URL <CODE>/</CODE> to <CODE>/e/www/</CODE>. While is
seems
trivial it is actually trivial with mod_rewrite, only. Because the typical
-old mechanisms of URL <i>Aliases</i> (as provides by mod_alias and friends)
-only used <i>prefix</i> matching. With this you cannot do such a redirection
+old mechanisms of URL <EM>Aliases</EM> (as provides by mod_alias and friends)
+only used <EM>prefix</EM> matching. With this you cannot do such a
redirection
because the DocumentRoot is a prefix of all URLs. With mod_rewrite it is
really trivial:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteRule <b>^/$</b> /e/www/ [<b>R</b>]
+RewriteRule <STRONG>^/$</STRONG> /e/www/ [<STRONG>R</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -159,9 +159,9 @@
<DD>
Every webmaster can sing a song about the problem of the trailing slash on
URLs referencing directories. If they are missing, the server dumps an error,
-because if you say <tt>/~quux/foo</tt> instead of
-<tt>/~quux/foo/</tt> then the server searches for a <i>file</i> named
-<tt>foo</tt>. And because this file is a directory it complains. Actually
+because if you say <CODE>/~quux/foo</CODE> instead of
+<CODE>/~quux/foo/</CODE> then the server searches for a <EM>file</EM> named
+<CODE>foo</CODE>. And because this file is a directory it complains. Actually
is tries to fix it themself in most of the cases, but sometimes this
mechanism
need to be emulated by you. For instance after you have done a lot of
complicated URL rewritings to CGI scripts etc.
@@ -175,27 +175,27 @@
internal rewrite, this would only work for the directory page, but would go
wrong when any images are included into this page with relative URLs, because
the browser would request an in-lined object. For instance, a request for
-<tt>image.gif</tt> in <tt>/~quux/foo/index.html</tt> would become
-<tt>/~quux/image.gif</tt> without the external redirect!
+<CODE>image.gif</CODE> in <CODE>/~quux/foo/index.html</CODE> would become
+<CODE>/~quux/image.gif</CODE> without the external redirect!
<P>
So, to do this trick we write:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
RewriteBase /~quux/
-RewriteRule ^foo<b>$</b> foo<b>/</b> [<b>R</b>]
+RewriteRule ^foo<STRONG>$</STRONG> foo<STRONG>/</STRONG>
[<STRONG>R</STRONG>]
</PRE></TD></TR></TABLE>
<P>
The crazy and lazy can even do the following in the top-level
-<tt>.htaccess</tt> file of their homedir. But notice that this creates some
+<CODE>.htaccess</CODE> file of their homedir. But notice that this creates
some
processing overhead.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
RewriteBase /~quux/
-RewriteCond %{REQUEST_FILENAME} <b>-d</b>
-RewriteRule ^(.+<b>[^/]</b>)$ $1<b>/</b> [R]
+RewriteCond %{REQUEST_FILENAME} <STRONG>-d</STRONG>
+RewriteRule ^(.+<STRONG>[^/]</STRONG>)$ $1<STRONG>/</STRONG>
[R]
</PRE></TD></TR></TABLE>
</DL>
@@ -209,7 +209,7 @@
<DD>
We want to create a homogenous and consistent URL layout over all WWW servers
on a Intranet webcluster, i.e. all URLs (per definition server local and thus
-server dependent!) become actually server <i>independed</i>! What we want is
+server dependent!) become actually server <EM>independed</EM>! What we want
is
to give the WWW namespace a consistent server-independend layout: no URL
should have to include any physically correct target server. The cluster
itself should drive us automatically to the physical target host.
@@ -227,7 +227,7 @@
: :
</PRE><P>
-We put them into files <tt>map.xxx-to-host</tt>. Second we need to instruct
+We put them into files <CODE>map.xxx-to-host</CODE>. Second we need to
instruct
all servers to redirect URLs of the forms
<P><PRE>
@@ -255,9 +255,9 @@
RewriteMap group-to-host txt:/path/to/map.group-to-host
RewriteMap entity-to-host txt:/path/to/map.entity-to-host
-RewriteRule ^/u/<b>([^/]+)</b>/?(.*)
http://<b>${user-to-host:$1|server0}</b>/u/$1/$2
-RewriteRule ^/g/<b>([^/]+)</b>/?(.*)
http://<b>${group-to-host:$1|server0}</b>/g/$1/$2
-RewriteRule ^/e/<b>([^/]+)</b>/?(.*)
http://<b>${entity-to-host:$1|server0}</b>/e/$1/$2
+RewriteRule ^/u/<STRONG>([^/]+)</STRONG>/?(.*)
http://<STRONG>${user-to-host:$1|server0}</STRONG>/u/$1/$2
+RewriteRule ^/g/<STRONG>([^/]+)</STRONG>/?(.*)
http://<STRONG>${group-to-host:$1|server0}</STRONG>/g/$1/$2
+RewriteRule ^/e/<STRONG>([^/]+)</STRONG>/?(.*)
http://<STRONG>${entity-to-host:$1|server0}</STRONG>/e/$1/$2
RewriteRule ^/([uge])/([^/]+)/?$ /$1/$2/.www/
RewriteRule ^/([uge])/([^/]+)/([^.]+.+) /$1/$2/.www/$3\
@@ -281,12 +281,12 @@
<DT><STRONG>Solution:</STRONG>
<DD>
The solution is trivial with mod_rewrite. On the old webserver we just
-redirect all <tt>/~user/anypath</tt> URLs to
-<tt>http://newserver/~user/anypath</tt>.
+redirect all <CODE>/~user/anypath</CODE> URLs to
+<CODE>http://newserver/~user/anypath</CODE>.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteRule ^/~(.+) http://<b>newserver</b>/~$1 [R,L]
+RewriteRule ^/~(.+) http://<STRONG>newserver</STRONG>/~$1 [R,L]
</PRE></TD></TR></TABLE>
</DL>
@@ -300,9 +300,9 @@
<DD>
Some sites with thousend of users usually use a structured homedir layout,
i.e. each homedir is in a subdirectory which begins for instance with the
-first character of the username. So, <tt>/~foo/anypath</tt> is
-<tt>/home/<b>f</b>/foo/.www/anypath</tt> while <tt>/~bar/anypath</tt> is
-<tt>/home/<b>b</b>/bar/.www/anypath</tt>.
+first character of the username. So, <CODE>/~foo/anypath</CODE> is
+<CODE>/home/<STRONG>f</STRONG>/foo/.www/anypath</CODE> while
<CODE>/~bar/anypath</CODE> is
+<CODE>/home/<STRONG>b</STRONG>/bar/.www/anypath</CODE>.
<P>
<DT><STRONG>Solution:</STRONG>
@@ -312,7 +312,7 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteRule ^/~(<b>([a-z])</b>[a-z0-9]+)(.*) /home/<b>$2</b>/$1/.www$3
+RewriteRule ^/~(<STRONG>([a-z])</STRONG>[a-z0-9]+)(.*)
/home/<STRONG>$2</STRONG>/$1/.www$3
</PRE></TD></TR></TABLE>
</DL>
@@ -325,10 +325,10 @@
<DT><STRONG>Description:</STRONG>
<DD>
This really is a hardcore example: a killer application which heavily uses
-per-directory <tt>RewriteRules</tt> to get a smooth look and feel on the Web
+per-directory <CODE>RewriteRules</CODE> to get a smooth look and feel on the
Web
while its data structure is never touched or adjusted.
-Background: <b><i>net.sw</i></b> is my archive of freely available Unix
+Background: <STRONG><EM>net.sw</EM></STRONG> is my archive of freely
available Unix
software packages, which I started to collect in 1992. It is both my hobby
and
job to to this, because while I'm studying computer science I have also
worked
for many years as a system and network administrator in my spare time. Every
@@ -355,8 +355,8 @@
</PRE><P>
In July 1996 I decided to make this 350 MB archive public to the world via a
-nice Web interface (<a href="http://net.sw.engelschall.com/net.sw/";><tt>
-http://net.sw.engelschall.com/net.sw/</tt></a>). "Nice" means that I wanted
to
+nice Web interface (<A HREF="http://net.sw.engelschall.com/net.sw/";><CODE>
+http://net.sw.engelschall.com/net.sw/</CODE></a>). "Nice" means that I
wanted to
offer a interface where you can browse directly through the archive
hierarchy.
And "nice" means that I didn't wanted to change anything inside this
hierarchy
- not even by putting some CGI scripts at the top of it. Why? Because the
@@ -368,7 +368,7 @@
<DD>
The solution has two parts: The first is a set of CGI scripts which create
all
the pages at all directory levels on-the-fly. I put them under
-<tt>/e/netsw/.www/</tt> as follows:
+<CODE>/e/netsw/.www/</CODE> as follows:
<P><PRE>
-rw-r--r-- 1 netsw users 1318 Aug 1 18:10 .wwwacl
@@ -386,18 +386,18 @@
-rw-r--r-- 1 netsw users 234 Jul 30 16:35 netsw-unlimit.lst
</PRE><P>
-The <tt>DATA/</tt> subdirectory holds the above directory structure, i.e.
the
-real <b><i>net.sw</i></b> stuff and gets automatically updated via
-<tt>rdist</tt> from time to time.
+The <CODE>DATA/</CODE> subdirectory holds the above directory structure,
i.e. the
+real <STRONG><EM>net.sw</EM></STRONG> stuff and gets automatically updated
via
+<CODE>rdist</CODE> from time to time.
The second part of the problem remains: how to link these two structures
-together into one smooth-looking URL tree? We want to hide the <tt>DATA/</tt>
+together into one smooth-looking URL tree? We want to hide the
<CODE>DATA/</CODE>
directory from the user while running the appropriate CGI scripts for the
various URLs.
Here is the solution: first I put the following into the per-directory
configuration file in the Document Root of the server to rewrite the
announced
-URL <tt>/net.sw/</tt> to the internal path <tt>/e/netsw</tt>:
+URL <CODE>/net.sw/</CODE> to the internal path <CODE>/e/netsw</CODE>:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteRule ^net.sw$ net.sw/ [R]
@@ -407,7 +407,7 @@
<P>
The first rule is for requests which miss the trailing slash! The second
rule
does the real thing. And then comes the killer configuration which stays in
-the per-directory config file <tt>/e/netsw/.www/.wwwacl</tt>:
+the per-directory config file <CODE>/e/netsw/.www/.wwwacl</CODE>:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
Options ExecCGI FollowSymLinks Includes MultiViews
@@ -461,11 +461,11 @@
<DD>
When switching from the NCSA webserver to the more modern Apache webserver a
lot of people want a smooth transition. So they want pages which use their
old
-NCSA <tt>imagemap</tt> program to work under Apache with the modern
-<tt>mod_imap</tt>. The problem is that there are a lot of
-hyperlinks around which reference the <tt>imagemap</tt> program via
-<tt>/cgi-bin/imagemap/path/to/page.map</tt>. Under Apache this
-has to read just <tt>/path/to/page.map</tt>.
+NCSA <CODE>imagemap</CODE> program to work under Apache with the modern
+<CODE>mod_imap</CODE>. The problem is that there are a lot of
+hyperlinks around which reference the <CODE>imagemap</CODE> program via
+<CODE>/cgi-bin/imagemap/path/to/page.map</CODE>. Under Apache this
+has to read just <CODE>/path/to/page.map</CODE>.
<P>
<DT><STRONG>Solution:</STRONG>
@@ -499,13 +499,13 @@
# first try to find it in custom/...
# ...and if found stop and be happy:
-RewriteCond /your/docroot/<b>dir1</b>/%{REQUEST_FILENAME} -f
-RewriteRule ^(.+) /your/docroot/<b>dir1</b>/$1 [L]
+RewriteCond /your/docroot/<STRONG>dir1</STRONG>/%{REQUEST_FILENAME}
-f
+RewriteRule ^(.+) /your/docroot/<STRONG>dir1</STRONG>/$1 [L]
# second try to find it in pub/...
# ...and if found stop and be happy:
-RewriteCond /your/docroot/<b>dir2</b>/%{REQUEST_FILENAME} -f
-RewriteRule ^(.+) /your/docroot/<b>dir2</b>/$1 [L]
+RewriteCond /your/docroot/<STRONG>dir2</STRONG>/%{REQUEST_FILENAME}
-f
+RewriteRule ^(.+) /your/docroot/<STRONG>dir2</STRONG>/$1 [L]
# else go on for other Alias or ScriptAlias directives,
# etc.
@@ -530,13 +530,13 @@
<DD>
We use a rewrite rule to strip out the status information and remember it via
an environment variable which can be later dereferenced from within XSSI or
-CGI. This way a URL <tt>/foo/S=java/bar/</tt> gets translated to
-<tt>/foo/bar/</tt> and the environment variable named <tt>STATUS</tt> is set
+CGI. This way a URL <CODE>/foo/S=java/bar/</CODE> gets translated to
+<CODE>/foo/bar/</CODE> and the environment variable named
<CODE>STATUS</CODE> is set
to the value "java".
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteRule ^(.*)/<b>S=([^/]+)</b>/(.*) $1/$3 [E=<b>STATUS:$2</b>]
+RewriteRule ^(.*)/<STRONG>S=([^/]+)</STRONG>/(.*) $1/$3
[E=<STRONG>STATUS:$2</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -548,7 +548,7 @@
<DL>
<DT><STRONG>Description:</STRONG>
<DD>
-Assume that you want to provide <tt>www.<b>username</b>.host.domain.com</tt>
+Assume that you want to provide
<CODE>www.<STRONG>username</STRONG>.host.domain.com</CODE>
for the homepage of username via just DNS A records to the same machine and
without any virtualhosts on this machine.
@@ -557,14 +557,14 @@
<DD>
For HTTP/1.0 requests there is no solution, but for HTTP/1.1 requests which
contain a Host: HTTP header we can use the following ruleset to rewrite
-<tt>http://www.username.host.com/anypath</tt> internally to
-<tt>/home/username/anypath</tt>:
+<CODE>http://www.username.host.com/anypath</CODE> internally to
+<CODE>/home/username/anypath</CODE>:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteCond %{<b>HTTP_HOST</b>}
^www\.<b>[^.]+</b>\.host\.com$
+RewriteCond %{<STRONG>HTTP_HOST</STRONG>}
^www\.<STRONG>[^.]+</STRONG>\.host\.com$
RewriteRule ^(.+) %{HTTP_HOST}$1 [C]
-RewriteRule ^www\.<b>([^.]+)</b>\.host\.com(.*) /home/<b>$1</b>$2
+RewriteRule ^www\.<STRONG>([^.]+)</STRONG>\.host\.com(.*)
/home/<STRONG>$1</STRONG>$2
</PRE></TD></TR></TABLE>
</DL>
@@ -577,8 +577,8 @@
<DT><STRONG>Description:</STRONG>
<DD>
We want to redirect homedir URLs to another webserver
-<tt>www.somewhere.com</tt> when the requesting user does not stay in the
local
-domain <tt>ourdomain.com</tt>. This is sometimes used in virtual host
+<CODE>www.somewhere.com</CODE> when the requesting user does not stay in the
local
+domain <CODE>ourdomain.com</CODE>. This is sometimes used in virtual host
contexts.
<P>
@@ -588,7 +588,7 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteCond %{REMOTE_HOST} <b>!^.+\.ourdomain\.com$</b>
+RewriteCond %{REMOTE_HOST} <STRONG>!^.+\.ourdomain\.com$</STRONG>
RewriteRule ^(/~.+) http://www.somewhere.com/$1 [R,L]
</PRE></TD></TR></TABLE>
@@ -614,8 +614,8 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteCond /your/docroot/%{REQUEST_FILENAME} <b>!-f</b>
-RewriteRule ^(.+)
http://<b>webserverB</b>.dom/$1
+RewriteCond /your/docroot/%{REQUEST_FILENAME} <STRONG>!-f</STRONG>
+RewriteRule ^(.+)
http://<STRONG>webserverB</STRONG>.dom/$1
</PRE></TD></TR></TABLE>
<P>
@@ -625,8 +625,8 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteCond %{REQUEST_URI} <b>!-U</b>
-RewriteRule ^(.+) http://<b>webserverB</b>.dom/$1
+RewriteCond %{REQUEST_URI} <STRONG>!-U</STRONG>
+RewriteRule ^(.+) http://<STRONG>webserverB</STRONG>.dom/$1
</PRE></TD></TR></TABLE>
<P>
@@ -657,7 +657,7 @@
<DD>
We have to use a kludge by the use of a NPH-CGI script which does the
redirect
itself. Because here no escaping is done (NPH=non-parseable headers). First
-we introduce a new URL scheme <tt>xredirect:</tt> by the following per-server
+we introduce a new URL scheme <CODE>xredirect:</CODE> by the following
per-server
config-line (should be one of the last rewrite rules):
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
@@ -666,8 +666,8 @@
</PRE></TD></TR></TABLE>
<P>
-This forces all URLs prefixed with <tt>xredirect:</tt> to be piped through
the
-<tt>nph-xredirect.cgi</tt> program. And this program just looks like:
+This forces all URLs prefixed with <CODE>xredirect:</CODE> to be piped
through the
+<CODE>nph-xredirect.cgi</CODE> program. And this program just looks like:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
<PRE>
@@ -691,7 +691,7 @@
print "</head>\n";
print "<body>\n";
print "<h1>Moved Temporarily (EXTENDED)</h1>\n";
-print "The document has moved <a
href=\"$url\">here</a>.<p>\n";
+print "The document has moved <a
HREF=\"$url\">here</a>.<p>\n";
print "</body>\n";
print "</html>\n";
@@ -702,7 +702,7 @@
<P>
This provides you with the functionality to do redirects to all URL schemes,
i.e. including the one which are not directly accepted by mod_rewrite. For
-instance you can now also redirect to <tt>news:newsgroup</tt> via
+instance you can now also redirect to <CODE>news:newsgroup</CODE> via
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteRule ^anyurl xredirect:news:newsgroup
@@ -710,7 +710,7 @@
<P>
Notice: You have not to put [R] or [R,L] to the above rule because the
-<tt>xredirect:</tt> need to be expanded later by our special "pipe through"
+<CODE>xredirect:</CODE> need to be expanded later by our special "pipe
through"
rule above.
</DL>
@@ -722,8 +722,8 @@
<DL>
<DT><STRONG>Description:</STRONG>
<DD>
-Do you know the great CPAN (Comprehensive Perl Archive Network) under <a
-href="http://www.perl.com/CPAN";>http://www.perl.com/CPAN</a>? This does a
+Do you know the great CPAN (Comprehensive Perl Archive Network) under <A
+HREF="http://www.perl.com/CPAN";>http://www.perl.com/CPAN</a>? This does a
redirect to one of several FTP servers around the world which carry a CPAN
mirror and is approximately near the location of the requesting client.
Actually this can be called an FTP access multiplexing service. While CPAN
@@ -741,7 +741,7 @@
RewriteEngine on
RewriteMap multiplex txt:/path/to/map.cxan
RewriteRule ^/CxAN/(.*) %{REMOTE_HOST}::$1 [C]
-RewriteRule ^.+\.<b>([a-zA-Z]+)</b>::(.*)$
${multiplex:<b>$1</b>|ftp.default.dom}$2 [R,L]
+RewriteRule ^.+\.<STRONG>([a-zA-Z]+)</STRONG>::(.*)$
${multiplex:<STRONG>$1</STRONG>|ftp.default.dom}$2 [R,L]
</PRE></TD></TR></TABLE>
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
@@ -772,7 +772,7 @@
<P>
<DT><STRONG>Solution:</STRONG>
<DD>
-There are a lot of variables named <tt>TIME_xxx</tt> for rewrite conditions.
+There are a lot of variables named <CODE>TIME_xxx</CODE> for rewrite
conditions.
In conjunction with the special lexicographic comparison patterns <STRING,
>STRING and =STRING we can do time-dependend redirects:
@@ -785,9 +785,9 @@
</PRE></TD></TR></TABLE>
<P>
-This provides the content of <tt>foo.day.html</tt> under the URL
-<tt>foo.html</tt> from 07:00-19:00 and at the remaining time the contents of
-<tt>foo.night.html</tt>. Just a nice feature for a homepage...
+This provides the content of <CODE>foo.day.html</CODE> under the URL
+<CODE>foo.html</CODE> from 07:00-19:00 and at the remaining time the
contents of
+<CODE>foo.night.html</CODE>. Just a nice feature for a homepage...
</DL>
@@ -837,8 +837,8 @@
<DL>
<DT><STRONG>Description:</STRONG>
<DD>
-Assume we have recently renamed the page <tt>bar.html</tt> to
-<tt>foo.html</tt> and now want to provide the old URL for backward
+Assume we have recently renamed the page <CODE>bar.html</CODE> to
+<CODE>foo.html</CODE> and now want to provide the old URL for backward
compatibility. Actually we want that users of the old URL even not recognize
that the pages was renamed.
@@ -850,7 +850,7 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
RewriteBase /~quux/
-RewriteRule ^<b>foo</b>\.html$ <b>bar</b>.html
+RewriteRule ^<STRONG>foo</STRONG>\.html$ <STRONG>bar</STRONG>.html
</PRE></TD></TR></TABLE>
</DL>
@@ -862,8 +862,8 @@
<DL>
<DT><STRONG>Description:</STRONG>
<DD>
-Assume again that we have recently renamed the page <tt>bar.html</tt> to
-<tt>foo.html</tt> and now want to provide the old URL for backward
+Assume again that we have recently renamed the page <CODE>bar.html</CODE> to
+<CODE>foo.html</CODE> and now want to provide the old URL for backward
compatibility. But this time we want that the users of the old URL get hinted
to the new one, i.e. their browsers Location field should change, too.
@@ -876,7 +876,7 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
RewriteBase /~quux/
-RewriteRule ^<b>foo</b>\.html$ <b>bar</b>.html [<b>R</b>]
+RewriteRule ^<STRONG>foo</STRONG>\.html$ <STRONG>bar</STRONG>.html
[<STRONG>R</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -899,21 +899,21 @@
We cannot use content negotiation because the browsers do not provide their
type in that form. Instead we have to act on the HTTP header "User-Agent".
The following condig does the following: If the HTTP header "User-Agent"
-begins with "Mozilla/3", the page <tt>foo.html</tt> is rewritten to
-<tt>foo.NS.html</tt> and and the rewriting stops. If the browser is "Lynx"
or
-"Mozilla" of version 1 or 2 the URL becomes <tt>foo.20.html</tt>. All other
-browsers receive page <tt>foo.32.html</tt>. This is done by the following
+begins with "Mozilla/3", the page <CODE>foo.html</CODE> is rewritten to
+<CODE>foo.NS.html</CODE> and and the rewriting stops. If the browser is
"Lynx" or
+"Mozilla" of version 1 or 2 the URL becomes <CODE>foo.20.html</CODE>. All
other
+browsers receive page <CODE>foo.32.html</CODE>. This is done by the following
ruleset:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteCond %{HTTP_USER_AGENT} ^<b>Mozilla/3</b>.*
-RewriteRule ^foo\.html$ foo.<b>NS</b>.html [<b>L</b>]
+RewriteCond %{HTTP_USER_AGENT} ^<STRONG>Mozilla/3</STRONG>.*
+RewriteRule ^foo\.html$ foo.<STRONG>NS</STRONG>.html
[<STRONG>L</STRONG>]
-RewriteCond %{HTTP_USER_AGENT} ^<b>Lynx/</b>.* [OR]
-RewriteCond %{HTTP_USER_AGENT} ^<b>Mozilla/[12]</b>.*
-RewriteRule ^foo\.html$ foo.<b>20</b>.html [<b>L</b>]
+RewriteCond %{HTTP_USER_AGENT} ^<STRONG>Lynx/</STRONG>.* [OR]
+RewriteCond %{HTTP_USER_AGENT} ^<STRONG>Mozilla/[12]</STRONG>.*
+RewriteRule ^foo\.html$ foo.<STRONG>20</STRONG>.html
[<STRONG>L</STRONG>]
-RewriteRule ^foo\.html$ foo.<b>32</b>.html [<b>L</b>]
+RewriteRule ^foo\.html$ foo.<STRONG>32</STRONG>.html
[<STRONG>L</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -926,9 +926,9 @@
<DT><STRONG>Description:</STRONG>
<DD>
Assume there are nice webpages on remote hosts we want to bring into our
-namespace. For FTP servers we would use the <tt>mirror</tt> program which
+namespace. For FTP servers we would use the <CODE>mirror</CODE> program which
actually maintains an explicit up-to-date copy of the remote data on the
local
-machine. For a webserver we could use the program <tt>webcopy</tt> which acts
+machine. For a webserver we could use the program <CODE>webcopy</CODE> which
acts
similar via HTTP. But both techniques have one major drawback: The local copy
is always just as up-to-date as often we run the program. It would be much
better if the mirror is not a static one we have to establish explicitly.
@@ -945,13 +945,13 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
RewriteBase /~quux/
-RewriteRule ^<b>hotsheet/</b>(.*)$
<b>http://www.tstimpreso.com/hotsheet/</b>$1 [<b>P</b>]
+RewriteRule ^<STRONG>hotsheet/</STRONG>(.*)$
<STRONG>http://www.tstimpreso.com/hotsheet/</STRONG>$1 [<STRONG>P</STRONG>]
</PRE></TD></TR></TABLE>
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
RewriteBase /~quux/
-RewriteRule ^<b>usa-news\.html</b>$
<b>http://www.quux-corp.com/news/index.html</b> [<b>P</b>]
+RewriteRule ^<STRONG>usa-news\.html</STRONG>$
<STRONG>http://www.quux-corp.com/news/index.html</STRONG> [<STRONG>P</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -985,9 +985,9 @@
<DT><STRONG>Description:</STRONG>
<DD>
This is a tricky way of virtually running a corporates (external) Internet
-webserver (<tt>www.quux-corp.dom</tt>), while actually keeping and
maintaining
+webserver (<CODE>www.quux-corp.dom</CODE>), while actually keeping and
maintaining
its data on a (internal) Intranet webserver
-(<tt>www2.quux-corp.dom</tt>) which is protected by a firewall. The
+(<CODE>www2.quux-corp.dom</CODE>) which is protected by a firewall. The
trick is that on the external webserver we retrieve the requested data
on-the-fly from the internal one.
@@ -1000,8 +1000,8 @@
firewall ruleset like the following:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-<b>ALLOW</b> Host www.quux-corp.dom Port >1024 --> Host
www2.quux-corp.dom Port <b>80</b>
-<b>DENY</b> Host * Port * --> Host
www2.quux-corp.dom Port <b>80</b>
+<STRONG>ALLOW</STRONG> Host www.quux-corp.dom Port >1024 --> Host
www2.quux-corp.dom Port <STRONG>80</STRONG>
+<STRONG>DENY</STRONG> Host * Port * --> Host
www2.quux-corp.dom Port <STRONG>80</STRONG>
</PRE></TD></TR></TABLE>
<P>
@@ -1011,9 +1011,9 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteRule ^/~([^/]+)/?(.*) /home/$1/.www/$2
-RewriteCond %{REQUEST_FILENAME} <b>!-f</b>
-RewriteCond %{REQUEST_FILENAME} <b>!-d</b>
-RewriteRule ^/home/([^/]+)/.www/?(.*)
http://<b>www2</b>.quux-corp.dom/~$1/pub/$2 [<b>P</b>]
+RewriteCond %{REQUEST_FILENAME} <STRONG>!-f</STRONG>
+RewriteCond %{REQUEST_FILENAME} <STRONG>!-d</STRONG>
+RewriteRule ^/home/([^/]+)/.www/?(.*)
http://<STRONG>www2</STRONG>.quux-corp.dom/~$1/pub/$2 [<STRONG>P</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -1025,8 +1025,8 @@
<DL>
<DT><STRONG>Description:</STRONG>
<DD>
-Suppose we want to load balance the traffic to <tt>www.foo.com</tt> over
-<tt>www[0-5].foo.com</tt> (a total of 6 servers). How can this be done?
+Suppose we want to load balance the traffic to <CODE>www.foo.com</CODE> over
+<CODE>www[0-5].foo.com</CODE> (a total of 6 servers). How can this be done?
<P>
<DT><STRONG>Solution:</STRONG>
@@ -1035,11 +1035,11 @@
a commonly known DNS-based variant and then the special one with mod_rewrite:
<ol>
-<li><b>DNS Round-Robin</b>
+<li><STRONG>DNS Round-Robin</STRONG>
<P>
The simplest method for load-balancing is to use the DNS round-robin feature
-of BIND. Here you just configure <tt>www[0-9].foo.com</tt> as usual in your
+of BIND. Here you just configure <CODE>www[0-9].foo.com</CODE> as usual in
your
DNS with A(address) records, e.g.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
@@ -1066,33 +1066,33 @@
<P>
Notice that this seems wrong, but is actually an intended feature of BIND and
-can be used in this way. However, now when <tt>www.foo.com</tt> gets
resolved,
-BIND gives out <tt>www0-www6</tt> - but in a slightly permutated/rotated
order
+can be used in this way. However, now when <CODE>www.foo.com</CODE> gets
resolved,
+BIND gives out <CODE>www0-www6</CODE> - but in a slightly permutated/rotated
order
every time. This way the clients are spread over the various servers.
But notice that this not a perfect load balancing scheme, because DNS resolve
information gets cached by the other nameservers on the net, so once a client
-has resolved <tt>www.foo.com</tt> to a particular <tt>wwwN.foo.com</tt>, all
-subsequent requests also go to this particular name <tt>wwwN.foo.com</tt>.
But
+has resolved <CODE>www.foo.com</CODE> to a particular
<CODE>wwwN.foo.com</CODE>, all
+subsequent requests also go to this particular name
<CODE>wwwN.foo.com</CODE>. But
the final result is ok, because the total sum of the requests are really
spread over the various webservers.
<P>
-<li><b>DNS Load-Balancing</b>
+<li><STRONG>DNS Load-Balancing</STRONG>
<P>
A sophisticated DNS-based method for load-balancing is to use the program
-<tt>lbnamed</tt> which can be found at <a
-href="http://www.stanford.edu/~schemers/docs/lbnamed/lbnamed.html";>http://www.stanford.edu/~schemers/docs/lbnamed/lbnamed.html</a>.
+<CODE>lbnamed</CODE> which can be found at <A
+HREF="http://www.stanford.edu/~schemers/docs/lbnamed/lbnamed.html";>http://www.stanford.edu/~schemers/docs/lbnamed/lbnamed.html</a>.
It is a Perl 5 program in conjunction with auxilliary tools which provides a
real load-balancing for DNS.
<P>
-<li><b>Proxy Throughput Round-Robin</b>
+<li><STRONG>Proxy Throughput Round-Robin</STRONG>
<P>
In this variant we use mod_rewrite and its proxy throughput feature. First
we
-dedicate <tt>www0.foo.com</tt> to be actually <tt>www.foo.com</tt> by using a
+dedicate <CODE>www0.foo.com</CODE> to be actually <CODE>www.foo.com</CODE>
by using a
single
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
@@ -1100,11 +1100,11 @@
</PRE></TD></TR></TABLE>
<P>
-entry in the DNS. Then we convert <tt>www0.foo.com</tt> to a proxy-only
+entry in the DNS. Then we convert <CODE>www0.foo.com</CODE> to a proxy-only
server, i.e. we configure this machine so all arriving URLs are just pushed
-through the internal proxy to one of the 5 other servers
(<tt>www1-www5</tt>).
+through the internal proxy to one of the 5 other servers
(<CODE>www1-www5</CODE>).
To accomplish this we first establish a ruleset which contacts a load
-balancing script <tt>lb.pl</tt> for all URLs.
+balancing script <CODE>lb.pl</CODE> for all URLs.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
@@ -1113,7 +1113,7 @@
</PRE></TD></TR></TABLE>
<P>
-Then we write <tt>lb.pl</tt>:
+Then we write <CODE>lb.pl</CODE>:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
#!/path/to/perl
@@ -1139,13 +1139,13 @@
</PRE></TD></TR></TABLE>
<P>
-A last notice: Why is this useful? Seems like <tt>www0.foo.com</tt> still is
+A last notice: Why is this useful? Seems like <CODE>www0.foo.com</CODE>
still is
overloaded? The answer is yes, it is overloaded, but with plain proxy
throughput requests, only! All SSI, CGI, ePerl, etc. processing is completely
done on the other machines. This is the essential point.
<P>
-<li><b>Hardware/TCP Round-Robin</b>
+<li><STRONG>Hardware/TCP Round-Robin</STRONG>
<P>
There is a hardware solution available, too. Cisco has a beast called
@@ -1285,34 +1285,34 @@
feature for MIME-types is only appropriate when the CGI programs don't need
special URLs (actually PATH_INFO and QUERY_STRINGS) as their input.
-First, let us configure a new file type with extension <tt>.scgi</tt>
-(for secure CGI) which will be processed by the popular <tt>cgiwrap</tt>
+First, let us configure a new file type with extension <CODE>.scgi</CODE>
+(for secure CGI) which will be processed by the popular <CODE>cgiwrap</CODE>
program. The problem here is that for instance we use a Homogeneous URL
Layout
(see above) a file inside the user homedirs has the URL
-<tt>/u/user/foo/bar.scgi</tt>. But <tt>cgiwrap</tt> needs the URL in the form
-<tt>/~user/foo/bar.scgi/</tt>. The following rule solves the problem:
+<CODE>/u/user/foo/bar.scgi</CODE>. But <CODE>cgiwrap</CODE> needs the URL in
the form
+<CODE>/~user/foo/bar.scgi/</CODE>. The following rule solves the problem:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteRule ^/[uge]/<b>([^/]+)</b>/\.www/(.+)\.scgi(.*) ...
-... /internal/cgi/user/cgiwrap/~<b>$1</b>/$2.scgi$3
[NS,<b>T=application/x-http-cgi</b>]
+RewriteRule ^/[uge]/<STRONG>([^/]+)</STRONG>/\.www/(.+)\.scgi(.*) ...
+... /internal/cgi/user/cgiwrap/~<STRONG>$1</STRONG>/$2.scgi$3
[NS,<STRONG>T=application/x-http-cgi</STRONG>]
</PRE></TD></TR></TABLE>
<P>
Or assume we have some more nifty programs:
-<tt>wwwlog</tt> (which displays the <tt>access.log</tt> for a URL subtree and
-<tt>wwwidx</tt> (which runs Glimpse on a URL subtree). We have to
+<CODE>wwwlog</CODE> (which displays the <CODE>access.log</CODE> for a URL
subtree and
+<CODE>wwwidx</CODE> (which runs Glimpse on a URL subtree). We have to
provide the URL area to these programs so they know on which area
they have to act on. But usually this ugly, because they are all the
times still requested from that areas, i.e. typically we would run
-the <tt>swwidx</tt> program from within <tt>/u/user/foo/</tt> via
+the <CODE>swwidx</CODE> program from within <CODE>/u/user/foo/</CODE> via
hyperlink to
<P><PRE>
/internal/cgi/user/swwidx?i=/u/user/foo/
</PRE><P>
-which is ugly. Because we have to hard-code <b>both</b> the location of the
-area <b>and</b> the location of the CGI inside the hyperlink. When we have to
+which is ugly. Because we have to hard-code <STRONG>both</STRONG> the
location of the
+area <STRONG>and</STRONG> the location of the CGI inside the hyperlink. When
we have to
reorganise or area, we spend a lot of time changing the various hyperlinks.
<P>
@@ -1327,10 +1327,10 @@
</PRE></TD></TR></TABLE>
<P>
-Now the hyperlink to search at <tt>/u/user/foo/</tt> reads only
+Now the hyperlink to search at <CODE>/u/user/foo/</CODE> reads only
<P><PRE>
-href="*"
+HREF="*"
</PRE><P>
which internally gets automatically transformed to
@@ -1340,7 +1340,7 @@
</PRE><P>
The same approach leads to an invocation for the access log CGI
-program when the hyperlink <tt>:log</tt> gets used.
+program when the hyperlink <CODE>:log</CODE> gets used.
</DL>
@@ -1351,21 +1351,21 @@
<DL>
<DT><STRONG>Description:</STRONG>
<DD>
-How can we transform a static page <tt>foo.html</tt> into a dynamic variant
-<tt>foo.cgi</tt> in a seemless way, i.e. without notice by the browser/user.
+How can we transform a static page <CODE>foo.html</CODE> into a dynamic
variant
+<CODE>foo.cgi</CODE> in a seemless way, i.e. without notice by the
browser/user.
<P>
<DT><STRONG>Solution:</STRONG>
<DD>
We just rewrite the URL to the CGI-script and force the correct MIME-type so
it gets really run as a CGI-script. This way a request to
-<tt>/~quux/foo.html</tt> internally leads to the invokation of
-<tt>/~quux/foo.cgi</tt>.
+<CODE>/~quux/foo.html</CODE> internally leads to the invokation of
+<CODE>/~quux/foo.cgi</CODE>.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
RewriteBase /~quux/
-RewriteRule ^foo\.<b>html</b>$ foo.<b>cgi</b>
[T=<b>application/x-httpd-cgi</b>]
+RewriteRule ^foo\.<STRONG>html</STRONG>$ foo.<STRONG>cgi</STRONG>
[T=<STRONG>application/x-httpd-cgi</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -1390,18 +1390,18 @@
This is done via the following ruleset:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteCond %{REQUEST_FILENAME} <b>!-s</b>
-RewriteRule ^page\.<b>html</b>$ page.<b>cgi</b>
[T=application/x-httpd-cgi,L]
+RewriteCond %{REQUEST_FILENAME} <STRONG>!-s</STRONG>
+RewriteRule ^page\.<STRONG>html</STRONG>$ page.<STRONG>cgi</STRONG>
[T=application/x-httpd-cgi,L]
</PRE></TD></TR></TABLE>
<P>
-Here a request to <tt>page.html</tt> leads to a internal run of a
-corresponding <tt>page.cgi</tt> if <tt>page.html</tt> is still missing or has
-filesize null. The trick here is that <tt>page.cgi</tt> is a usual CGI script
+Here a request to <CODE>page.html</CODE> leads to a internal run of a
+corresponding <CODE>page.cgi</CODE> if <CODE>page.html</CODE> is still
missing or has
+filesize null. The trick here is that <CODE>page.cgi</CODE> is a usual CGI
script
which (additionally to its STDOUT) writes its output to the file
-<tt>page.html</tt>. Once it was run, the server sends out the data of
-<tt>page.html</tt>. When the webmaster wants to force a refresh the contents,
-he just removes <tt>page.html</tt> (usually done by a cronjob).
+<CODE>page.html</CODE>. Once it was run, the server sends out the data of
+<CODE>page.html</CODE>. When the webmaster wants to force a refresh the
contents,
+he just removes <CODE>page.html</CODE> (usually done by a cronjob).
</DL>
@@ -1421,7 +1421,7 @@
<DD>
No! We just combine the MIME multipart feature, the webserver NPH feature and
the URL manipulation power of mod_rewrite. First, we establish a new URL
-feature: Adding just <tt>:refresh</tt> to any URL causes this to be refreshed
+feature: Adding just <CODE>:refresh</CODE> to any URL causes this to be
refreshed
every time it gets updated on the filesystem.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
@@ -1557,7 +1557,7 @@
<DL>
<DT><STRONG>Description:</STRONG>
<DD>
-The <tt><VirtualHost></tt> feature of Apache is nice and works great
+The <CODE><VirtualHost></CODE> feature of Apache is nice and works
great
when you just have a few dozens virtual hosts. But when you are an ISP and
have hundreds of virtual hosts to provide this feature is not the best
choice.
@@ -1640,14 +1640,14 @@
<DT><STRONG>Description:</STRONG>
<DD>
How can we block a really annoying robot from retrieving pages of a specific
-webarea? A <tt>/robots.txt</tt> file containing entries of the "Robot
+webarea? A <CODE>/robots.txt</CODE> file containing entries of the "Robot
Exclusion Protocol" is typically not enough to get rid of such a robot.
<P>
<DT><STRONG>Solution:</STRONG>
<DD>
We use a ruleset which forbids the URLs of the webarea
-<tt>/~quux/foo/arc/</tt> (perhaps a very deep directory indexed area where
the
+<CODE>/~quux/foo/arc/</CODE> (perhaps a very deep directory indexed area
where the
robot traversal would create big server load). We have to make sure that we
forbid access only to the particular robot, i.e. just forbidding the host
where the robot runs is not enough. This would block users from this host,
@@ -1655,9 +1655,9 @@
information.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteCond %{HTTP_USER_AGENT} ^<b>NameOfBadRobot</b>.*
-RewriteCond %{REMOTE_ADDR} ^<b>123\.45\.67\.[8-9]</b>$
-RewriteRule ^<b>/~quux/foo/arc/</b>.+ - [<b>F</b>]
+RewriteCond %{HTTP_USER_AGENT} ^<STRONG>NameOfBadRobot</STRONG>.*
+RewriteCond %{REMOTE_ADDR} ^<STRONG>123\.45\.67\.[8-9]</STRONG>$
+RewriteRule ^<STRONG>/~quux/foo/arc/</STRONG>.+ - [<STRONG>F</STRONG>]
</PRE></TD></TR></TABLE>
</DL>
@@ -1682,15 +1682,15 @@
a HTTP Referer header.
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteCond %{HTTP_REFERER} <b>!^$</b>
+RewriteCond %{HTTP_REFERER} <STRONG>!^$</STRONG>
RewriteCond %{HTTP_REFERER} !^http://www.quux-corp.de/~quux/.*$ [NC]
-RewriteRule <b>.*\.gif$</b> - [F]
+RewriteRule <STRONG>.*\.gif$</STRONG> -
[F]
</PRE></TD></TR></TABLE>
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !.*/foo-with-gif\.html$
-RewriteRule <b>^inlined-in-foo\.gif$</b> - [F]
+RewriteRule <STRONG>^inlined-in-foo\.gif$</STRONG> -
[F]
</PRE></TD></TR></TABLE>
</DL>
@@ -1760,19 +1760,19 @@
<DT><STRONG>Solution:</STRONG>
<DD>
We first have to make sure mod_rewrite is below(!) mod_proxy in the
-<tt>Configuration</tt> file when compiling the Apache webserver. This way it
+<CODE>Configuration</CODE> file when compiling the Apache webserver. This
way it
gets called _before_ mod_proxy. Then we configure the following for a
host-dependend deny...
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteCond %{REMOTE_HOST} <b>^badhost\.mydomain\.com$</b>
+RewriteCond %{REMOTE_HOST} <STRONG>^badhost\.mydomain\.com$</STRONG>
RewriteRule !^http://[^/.]\.mydomain.com.* - [F]
</PRE></TD></TR></TABLE>
<P>...and this one for a [EMAIL PROTECTED] deny:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteCond [EMAIL PROTECTED] <b>[EMAIL PROTECTED]</b>
+RewriteCond [EMAIL PROTECTED] <STRONG>[EMAIL PROTECTED]</STRONG>
RewriteRule !^http://[^/.]\.mydomain.com.* - [F]
</PRE></TD></TR></TABLE>
@@ -1796,9 +1796,9 @@
We use a list of rewrite conditions to exclude all except our friends:
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
-RewriteCond [EMAIL PROTECTED] <b>[EMAIL PROTECTED]</b>
-RewriteCond [EMAIL PROTECTED] <b>!^friend2</b>@client2.quux-corp\.com$
-RewriteCond [EMAIL PROTECTED] <b>!^friend3</b>@client3.quux-corp\.com$
+RewriteCond [EMAIL PROTECTED] <STRONG>[EMAIL PROTECTED]</STRONG>
+RewriteCond [EMAIL PROTECTED]
<STRONG>!^friend2</STRONG>@client2.quux-corp\.com$
+RewriteCond [EMAIL PROTECTED]
<STRONG>!^friend3</STRONG>@client3.quux-corp\.com$
RewriteRule ^/~quux/only-for-friends/ -
[F]
</PRE></TD></TR></TABLE>
@@ -1872,8 +1872,8 @@
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
RewriteEngine on
-RewriteMap quux-map <b>prg:</b>/path/to/map.quux.pl
-RewriteRule ^/~quux/(.*)$ /~quux/<b>${quux-map:$1}</b>
+RewriteMap quux-map <STRONG>prg:</STRONG>/path/to/map.quux.pl
+RewriteRule ^/~quux/(.*)$ /~quux/<STRONG>${quux-map:$1}</STRONG>
</PRE></TD></TR></TABLE>
<P><TABLE BGCOLOR="#E0E5F5" BORDER="0" CELLSPACING="0"
CELLPADDING="5"><TR><TD><PRE>
@@ -1893,9 +1893,9 @@
<P>
This is a demonstration-only example and just rewrites all URLs
-<tt>/~quux/foo/...</tt> to <tt>/~quux/bar/...</tt>. Actually you can program
-whatever you like. But notice that while such maps can be <b>used</b> also by
-an average user, only the system administrator can <b>define</b> it.
+<CODE>/~quux/foo/...</CODE> to <CODE>/~quux/bar/...</CODE>. Actually you can
program
+whatever you like. But notice that while such maps can be
<STRONG>used</STRONG> also by
+an average user, only the system administrator can <STRONG>define</STRONG>
it.
</DL>
