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<!-- addedByLfdynahead ver 1.4 --><TABLE ALIGN="right" border=0><TR><TD ALIGN="right"><FONT SIZE="-1" FACE="Arial,Helvetica">This document is available in: <A href="../../English/January2000/article129.shtml">English</a> <A href="../../Castellano/January2000/article129.html">Castellano</a> <A href="../../Deutsch/January2000/article129.shtml">Deutsch</a> <A href="../../Francais/January2000/article129.shtml">Francais</a> <A href="../../Italiano/January2000/article129.html">Italiano</a> <A href="../../Nederlands/January2000/article129.shtml">Nederlands</a> <A href="../../Turkce/January2000/article129.shtml">Turkce</a> <A href="../../Korean/January2000/article129.html">Korean</a> </FONT></TD></TR></TABLE><br>
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<br>
<IMG SRC="../../common/images/Atif-Ghaffar.jpg" ALT="[Photo of the Author]" HEIGHT=100 WIDTH=100>
<BR>by <A HREF="mailto:aghaffar@developer.ch">Atif Ghaffar</A>
<BR><BR>
<I>About the author:</I><BR>
<P>
I live and work in Switzerland as a webmaster/unix administrator.
My passions include, Linux, unix, Perl, Apache and GPL softwares.
More about me can be found on my <a href="http://www.developer.ch/~aghaffar">homepage</a><br></P>
<BR><i>Content</i>:
<UL>
<LI><A HREF="#lfindex0">Why should we recycle IP addresses?</A></LI>
<LI><A HREF="#lfindex1">How to recycle ip adresses?</A></LI>
<LI><A HREF="#lfindex2">Using wildcards, dynamic hostnames</A></LI>
<LI><A HREF="#lfindex3">My virtual hosts configuration file</A></LI>
<LI><A HREF="#lfindex4">Additional Resources</A></LI>
<LI><A HREF="http://cgi.linuxfocus.org/cgi-bin/lftalkback?anum=129&lang=en">Talkback form for this article</A></LI>
</UL>
</TD></TR></TABLE>
<!-- HEAD OF THE ARTICLE -->
<H2>Recycling Ip Addresses with Apache</H2>
<IMG SRC="../../common/images/illustration129.gif" ALT="[Illustration]" HSPACE=10 HEIGHT=133 WIDTH=360>
<!-- ABSTRACT OF THE ARTICLE -->
<P><i>Abstract</i>:
<P>
This article demonstrates how to serve multiple virtual webservers using the same ip address with Apache on Unix/Linux. The article assumes that the reader has some knowledge of Apache and DNS and unix.
<br>
The target audience of this article is ISPs, System Administrator and anyone who cares to read and learn.
</P>
<HR size="2" noshade align="right"><BR>
<!-- BODY OF THE ARTICLE -->
<A NAME="lfindex0"> </A>
<H2>Why should we recycle IP addresses?</H2>
<p>
Ip address recycling is useful for number of reasons.
<ol>
<li>one can easily run out of ip addresses
<li>one might have only one ip address (as in my case)
<li>More system administrators time to add interfaces to host to use multiple ip addresses.
</ol>
<A NAME="lfindex1"> </A>
<H2>How to recycle ip adresses?</H2>
Using Apache it is simple to serve multiple domains with a single ip address.<br>
For this article we will assume the ip address to be 192.168.1.1, and hostname hometranet.home.
<br>
Simply add a line like this to your httpd.conf file<br>
<xmp>
NameVirtualHost 192.168.1.1:80
</xmp>
<br>
<i>Next we will add three virtual servers using the same ip address</i>
<br>
<pre>
#Host for unix files
<VirtualHost 192.168.1.1:80>
ServerName unix.hometranet.home
DocumentRoot /www/unix/html
ScriptAlias /cgi-bin/ /www/unix/cgi-bin/
TransferLog /www/unix/logs/access_log
ErrorLog /www/unix/logs/error_log
</VirtualHost>
#Host for perl stuff
<VirtualHost 192.168.1.1:80>
ServerName perl.hometranet.home
DocumentRoot /www/perl/html
ScriptAlias /cgi-bin/ /www/perl/cgi-bin/
TransferLog /www/perl/logs/access_log
ErrorLog /www/perl/logs/error_log
</VirtualHost>
#Here we host some cool Apache stuff
<VirtualHost 192.168.1.1:80>
ServerName apache.hometranet.home
DocumentRoot /www/apache/html
ScriptAlias /cgi-bin/ /www/apache/cgi-bin/
TransferLog /www/apache/logs/access_log
ErrorLog /www/apache/logs/error_log
</VirtualHost>
</pre>
<i>
So using one ip address we have easily managed 3 different virtualhosts.<br>
<br>
Next add CNAMES or A Records for these names in your nameserver's <br>
zone file and dont forget to increment the serial number :)<br>
for eg: in my /var/named/hometranet.home.fwd, I would add<br>
</i>
<xmp>
perl.hometranet.home. IN A 192.168.1.1
apache.hometranet.home. IN A 192.168.1.1
unix.hometranet.home. IN A 192.168.1.1
</xmp>
<br>
Please note:
If you call this host by any other name than the ones given in the virtual config then the first virtual host will respond.
<br>
Before Apache 1.3.x the last one would have had responded.
<br>
For eg: If this host is named madmag then calling http://madmag.hometranet.home will give you the same result as calling unix.hometranet.home.
<br>
<A NAME="lfindex2"> </A>
<H2>Using wildcards, dynamic hostnames</H2>
<p>
This is the cool part. Apache allows wildcards to be used in hostanames.
<br>
Meaning you can set a domain *.home.hometranet.home and all queries to
user1.home.hometranet.home, user2.home.hometranet.home, user3.home.hometranet.home,etc
will be responded.
<br>
Example:
<br>
<pre>
#host for users
<VirtualHost 192.168.1.1:80>
ServerName home.hometranet.home
ServerAlias *.home.hometranet.home
DocumentRoot /www/home/html
TransferLog /www/home/logs/access_log
ErrorLog /www/home/logs/error_log
</VirtualHost>
and an entry in the named zone file.
*.home.hometranet.home. IN A 192.168.1.1
</pre>
Note: This trick will not work if you are using Microsoft DNS Server. Apparently it refuses to accept wildcards in hostnames.
<br>
(But you arent using one, are you??)
<br>
I once wrote a small system that allows users on the network to add their
CV in the database, and using the above trick, their CVs
were availabe by http://theirUserName.cv.developer.ch.
</p>
<A NAME="lfindex3"> </A>
<H2><a href="../../common/src/article129/vhosts.conf.txt">My virtual hosts configuration file</a></H2>
<p>
<a href="../../common/src/article129/vhosts.conf.txt">Here</a> is a bit more exhaustive configuration file that i have separated from my main httpd.conf file<br>
This one is actually on my server.<br>
<br>To include this file in the main httpd.conf you can use the <b>Include</b> directive in your main httpd.conf.
<br>Include "/etc/vhosts.conf"
</p>
<A NAME="lfindex4"> </A>
<H2>Additional Resources</H2>
<dl>
<dt>
[Apache name-based Virtual Host Support]
<dd>
<a href="http://www.apache.org/docs/vhosts/name-based.html">http://www.apache.org/docs/vhosts/name-based.html</a>
<dt>
[Apache Virtual Host documentation]
<dd>
<a href="http://www.apache.org/docs/vhosts/index.html">http://www.apache.org/docs/vhosts/index.html</a>
<dt>[An In-Depth Discussion of Virtual Host Matching]
<dd>
<a href="http://www.apache.org/docs/vhosts/details.html">http://www.apache.org/docs/vhosts/details.html</a>
</dl>
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<p><font size=1>2001-01-27, generated by lfparser version 2.8</font></p>
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