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diff --git a/docs/manual/vhosts/virtual-host.html b/docs/manual/vhosts/virtual-host.html deleted file mode 100644 index aa81fad91e..0000000000 --- a/docs/manual/vhosts/virtual-host.html +++ /dev/null @@ -1,208 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> -<HTML> -<HEAD> -<TITLE>Apache Server Virtual Host Support</TITLE> -</HEAD> - -<!-- Background white, links blue (unvisited), navy (visited), red (active) --> -<BODY - BGCOLOR="#FFFFFF" - TEXT="#000000" - LINK="#0000FF" - VLINK="#000080" - ALINK="#FF0000" -> -<!--#include virtual="header.html" --> -<H1 ALIGN="CENTER">Virtual Host Support</H1> - -<STRONG>See Also:</STRONG> -<A HREF="host.html">Non-IP based virtual hosts</A> - -<H2>What are virtual hosts?</H2> -This is the ability of a single machine to be a web server for multiple -domains. For example, an Internet service provider might have a machine -called <CODE>www.serve.com</CODE> which provides Web space for several -organizations including, say, <EM>smallco</EM> and <EM>baygroup</EM>. -Ordinarily, these groups would be given parts of the Web tree on www.serve.com. -So smallco's home page would have the URL -<BLOCKQUOTE> -http://www.serve.com/smallco/ -</BLOCKQUOTE> -and baygroup's home page would have the URL -<BLOCKQUOTE> -http://www.serve.com/baygroup/ -</BLOCKQUOTE> -<P> -For esthetic reasons, however, both organizations would rather their home -pages appeared under their own names rather than that of the service -provider's; but they do not want to set up their own Internet links and -servers. -<P> -Virtual hosts are the solution to this problem. smallco and baygroup would -have their own Internet name registrations, <CODE>www.smallco.com</CODE> and -<CODE>www.baygroup.org</CODE> respectively. These hostnames would both -correspond to the service provider's machine (www.serve.com). Thus -smallco's home page would now have the URL -<BLOCKQUOTE> -http://www.smallco.com/ -</BLOCKQUOTE> -and baygroup's home page would would have the URL -<BLOCKQUOTE> -http://www.baygroup.org/ -</BLOCKQUOTE> - -<H2>System requirements</H2> -Due to limitations in the HTTP/1.0 protocol, the web server <STRONG>must have a -different IP address for each virtual host</STRONG>. This can be achieved -by the machine having several physical network connections, or by use -of a <A HREF="../misc/vif-info.html">virtual interface</A> on some operating -systems. - -<H2>How to set up Apache</H2> -There are two ways of configuring apache to support multiple hosts. -Either by running a separate httpd daemon for each hostname, or by running a -single daemon which supports all the virtual hosts. -<P> -Use multiple daemons when: -<UL> -<LI>The different virtual hosts need very different httpd configurations, such - as different values for: - <A HREF="../mod/core.html#servertype">ServerType</A>, - <A HREF="../mod/core.html#user">User</A>, - <A HREF="../mod/core.html#group">Group</A>, - <A HREF="../mod/mod_mime.html#typesconfig">TypesConfig</A> or - <A HREF="../mod/core.html#serverroot">ServerRoot</A>. -<LI>The machine does not process a very high request rate. -</UL> -Use a single daemon when: -<UL> -<LI>Sharing of the httpd configuration between virtual hosts is acceptable. -<LI>The machine services a large number of requests, and so the performance - loss in running separate daemons may be significant. -</UL> - -<H2>Setting up multiple daemons</H2> -Create a separate httpd installation for each virtual host. -For each installation, use the -<A HREF="../mod/core.html#bindaddress">BindAddress</A> directive in the -configuration -file to select which IP address (or virtual host) that daemon services. -<EM>E.g.</EM>, -<BLOCKQUOTE><CODE>BindAddress www.smallco.com</CODE></BLOCKQUOTE> -This hostname can also be given as an IP address. - -<H2>Setting up a single daemon</H2> -For this case, a single httpd will service requests for all the virtual hosts. -The <A HREF="../mod/core.html#virtualhost">VirtualHost</A> directive in the - configuration file is used to set the values of -<A HREF="../mod/core.html#serveradmin">ServerAdmin</A>, -<A HREF="../mod/core.html#servername">ServerName</A>, -<A HREF="../mod/core.html#documentroot">DocumentRoot</A>, -<A HREF="../mod/core.html#errorlog">ErrorLog</A> and -<A HREF="../mod/mod_log_config.html#transferlog">TransferLog</A> configuration -directives to different values for each virtual host. -<EM>E.g.</EM>, -<BLOCKQUOTE><CODE> -<VirtualHost www.smallco.com><BR> -ServerAdmin webmaster@mail.smallco.com<BR> -DocumentRoot /groups/smallco/www<BR> -ServerName www.smallco.com<BR> -ErrorLog /groups/smallco/logs/error_log<BR> -TransferLog /groups/smallco/logs/access_log<BR> -</VirtualHost><BR> -<BR> -<VirtualHost www.baygroup.org><BR> -ServerAdmin webmaster@mail.baygroup.org<BR> -DocumentRoot /groups/baygroup/www<BR> -ServerName www.baygroup.org<BR> -ErrorLog /groups/baygroup/logs/error_log<BR> -TransferLog /groups/baygroup/logs/access_log<BR> -</VirtualHost><BR> -</CODE></BLOCKQUOTE> - -This VirtualHost hostnames can also be given as IP addresses. - -<P> - -Almost <STRONG>ANY</STRONG> configuration directive can be put -in the VirtualHost directive, with the exception of -<A HREF="../mod/core.html#servertype">ServerType</A>, -<A HREF="../mod/core.html#user">User</A>, -<A HREF="../mod/core.html#group">Group</A>, -<A HREF="../mod/core.html#startservers">StartServers</A>, -<A HREF="../mod/core.html#maxspareservers">MaxSpareServers</A>, -<A HREF="../mod/core.html#minspareservers">MinSpareServers</A>, -<A HREF="../mod/core.html#maxrequestsperchild">MaxRequestsPerChild</A>, -<A HREF="../mod/core.html#bindaddress">BindAddress</A>, -<A HREF="../mod/core.html#pidfile">PidFile</A>, -<A HREF="../mod/mod_mime.html#typesconfig">TypesConfig</A>, and -<A HREF="../mod/core.html#serverroot">ServerRoot</A>. - -<P> - -<EM>SECURITY:</EM> When specifying where to write log files, be aware -of some security risks which are present if anyone other than the -user that starts Apache has write access to the directory where they -are written. See the <A HREF="../misc/security_tips.html">security -tips</A> document for details. - -<P> - -<H2>File Handle/Resource Limits:</H2> -When using a large number of Virtual Hosts, Apache may run out of available -file descriptors if each Virtual Host specifies different log files. -The total number of file descriptors used by Apache is one for each distinct -error log file, one for every other log file directive, plus 10-20 for -internal use. Unix operating systems limit the number of file descriptors that -may be used by a process; the limit is typically 64, and may usually be -increased up to a large hard-limit. -<P> -Although Apache attempts to increase the limit as required, this -may not work if: -<OL> -<LI>Your system does not provide the setrlimit() system call. -<LI>The setrlimit(RLIMIT_NOFILE) call does not function on your system - (such as Solaris 2.3) -<LI>The number of file descriptors required exceeds the hard limit. -<LI>Your system imposes other limits on file descriptors, such as a limit -on stdio streams only using file descriptors below 256. (Solaris 2) -</OL> - -In the event of problems you can: -<UL> -<LI>Reduce the number of log files; don't specify log files in the VirtualHost -sections, but only log to the main log files. -<LI>If you system falls into 1 or 2 (above), then increase the file descriptor -limit before starting Apache, using a script like -<BLOCKQUOTE><CODE> -#!/bin/sh <BR> -ulimit -S -n 100 <BR> -exec httpd</CODE></BLOCKQUOTE> -</UL> - -The have been reports that Apache may start running out of resources allocated -for the root process. This will exhibit itself as errors in the error log like -"unable to fork". There are two ways you can bump this up: - -<OL> -<LI>Have a <CODE>csh</CODE> script wrapper around httpd which sets the -"rlimit" to some large number, like 512. -<LI>Edit http_main.c to add calls to setrlimit() from main(), along the lines -of -<PRE> - struct rlimit rlp; - - rlp.rlim_cur = rlp.rlim_max = 512; - if (setrlimit(RLIMIT_NPROC, &rlp)) { - fprintf(stderr, "setrlimit(RLIMIT_NPROC) failed.\n"); - exit(1); - } -</PRE> -(thanks to "Aaron Gifford <agifford@InfoWest.COM>" for the patch) -</OL> - -The latter will probably manifest itself in a later version of Apache. - -<!--#include virtual="footer.html" --> -</BODY> -</HTML> |