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| <h1 align="center">Server-Wide Configuration</h1> |
| |
| <p>This document explains some of the directives provided by |
| <a href="mod/core.html">core</A> server which are used to configure |
| the basic operations of the server.</p> |
| |
| <ul> |
| <li><a href="#identification">Server Identification</a></li> |
| <li><a href="#locations">File Locations</a></li> |
| <li><a href="#process">Process Creation</a></li> |
| <li><a href="#network">Network Configuration</a></li> |
| <li><a href="#resource">Limiting Resource Usage</a></li> |
| </ul> |
| |
| <hr> |
| |
| <h2><a name="identfication">Server Identification</a></h2> |
| |
| <table border="1"> |
| <tr><td valign="top"> |
| <strong>Related Directives</strong><br><br> |
| |
| <A HREF="mod/core.html#servername">ServerName</A><br> |
| <A HREF="mod/core.html#serveradmin">ServerAdmin</A><br> |
| <A HREF="mod/core.html#serversignature">ServerSignature</A><br> |
| <A HREF="mod/core.html#servertokens">ServerTokens</A><br> |
| <A HREF="mod/core.html#usecanonicalname">UseCanonicalName</A><br> |
| </td></tr></table> |
| |
| <p>The <code>ServerAdmin</code> and <code>ServerTokens</code> |
| directives control what information about the server will be presented |
| in server-generated documents such as error messages. |
| The <code>ServerTokens</code> directive sets the value of the |
| Server HTTP response header field.</p> |
| |
| <p>The <code>ServerName</code> and <code>UseCanonicalName</code> |
| directives are used by the server to determine how to construct |
| self-referential URLs. For example, when a client requests a |
| directory, but does not include the trailing slash in the directory |
| name, Apache must redirect the client to the full name including the |
| trailing slash so that the client will correctly resolve relative |
| references in the document.</p> |
| |
| <hr> |
| |
| <h2><a name="locations">File Locations</a></h2> |
| |
| <table border="1"> |
| <tr><td valign="top"> |
| <strong>Related Directives</strong><br><br> |
| |
| <a href="mod/core.html#coredumpdirectory">CoreDumpDirectory</a><br> |
| <a href="mod/core.html#documentroot">DocumentRoot</a><br> |
| <a href="mod/core.html#errorlog">ErrorLog</a><br> |
| <a href="mod/core.html#lockfile">Lockfile</a><br> |
| <a href="mod/core.html#pidfile">PidFile</a><br> |
| <a href="mod/core.html#scoreboardfile">ScoreBoardFile</a><br> |
| <a href="mod/core.html#serverroot">ServerRoot</a><br> |
| </td></tr></table> |
| |
| <p>These directives control the locations of the various files that |
| Apache needs for proper operation. When the pathname used does not |
| begin with a slash "/", the files are located relative to the |
| <code>ServerRoot</code>. Be careful about locating files in paths |
| which are writable by non-root users. See the <a |
| href="misc/security_tips.html">security tips</a> documentation for |
| more details.</p> |
| |
| <hr> |
| |
| <h2><a name="process">Process Creation</a></h2> |
| |
| <table border="1"> |
| <tr><td valign="top"> |
| <strong>Related Directives</strong><br><br> |
| |
| <a href="mod/core.html#bs2000account">BS2000Account</a><br> |
| <a href="mod/core.html#group">Group</a><br> |
| <a href="mod/core.html#baxclients">MaxClients</a><br> |
| <a href="mod/core.html#maxrequestsperchild">MaxRequestsPerChild</a><br> |
| <a href="mod/core.html#maxspareservers">MaxSpareServers</a><br> |
| <a href="mod/core.html#minspareservers">MinSpareServers</a><br> |
| <a href="mod/core.html#servertype">ServerType</a><br> |
| <a href="mod/core.html#startservers">StartServers</a><br> |
| <a href="mod/core.html#threadsperchild">ThreadsPerChild</a><br> |
| <a href="mod/core.html#user">User</a><br> |
| </td></tr></table> |
| |
| <p>When <code>ServerType</code> is set to its recommended value of |
| <code>Standalone</code>, Apache 1.3 for Unix is a pre-forking web |
| server. A single control process is responsible for launching child |
| processes which listen for connections and serve them when they |
| arrive. Apache always tries to maintain several <em>spare</em> or |
| idle server processes, which stand ready to serve incoming requests. |
| In this way, clients do not need to wait for a new child processes to |
| be forked before their requests can be served.</p> |
| |
| <p>The <code>StartServers</code>, <code>MinSpareServers</code>, |
| <code>MaxSpareServers</code>, and <code>MaxServers</code> regulate how |
| the parent process creates children to serve requests. In general, |
| Apache is very self-regulating, so most sites do not need to adjust |
| these directives from their default values. Sites which need to serve |
| more than 256 simultaneous requests may need to increase |
| <code>MaxClients</code>, while sites with limited memory may need to |
| decrease <code>MaxClients</code> to keep the server from thrashing |
| (swapping memory to disk and back).</p> |
| |
| <p>While the parent process is usually started as root under Unix |
| in order to bind to port 80, the child processes are launched |
| by Apache as a less-privileged user. The <code>User</code> and |
| <code>Group</code> directives are used to set the privileges |
| of the Apache child processes. The child processes must |
| be able to read all the content that will be served, but |
| should have as few privileges beyond that as possible. |
| In addition, unless <a href="suexec.html">suexec</a> is used, |
| these directives also set the privileges which will be inherited |
| by CGI scripts.</p> |
| |
| <p><code>MaxRequestsPerChild</code> controls how frequently the server |
| recycles processes by killing old ones and launching new ones.</p> |
| |
| <p>Under Windows, Apache launches one control process and one |
| child process. The child process creates multiple threads to |
| serve requests. The number of threads is controlled by the |
| <code>ThreadsPerChild</code> directive.</p> |
| |
| <hr> |
| |
| <h2><a name="network">Network Configuration</a></h2> |
| |
| <table border="1"> |
| <tr><td valign="top"> |
| <strong>Related Directives</strong><br><br> |
| |
| <a href="mod/core.html#bindaddress">BindAddress</a><br> |
| <a href="mod/core.html#keepalive">KeepAlive</a><br> |
| <a href="mod/core.html#keepalivetimeout">KeepAliveTimeout</a><br> |
| <a href="mod/core.html#listen">Listen</a><br> |
| <a href="mod/core.html#listenbacklog">ListenBackLog</a><br> |
| <a href="mod/core.html#maxKeepaliverequests">MaxKeepAliveRequests</a><br> |
| <a href="mod/core.html#port">Port</a><br> |
| <a href="mod/core.html#sendbuffersize">SendBufferSize</a><br> |
| <a href="mod/core.html#timeOut">TimeOut</a><br> |
| </td></tr></table> |
| |
| <p>When Apache starts, it connects to some port and address on the |
| local machine and waits for incoming requests. By default, it listens |
| to all addresses on the machine, and to the port as specified by the |
| <code>Port</code> directive in the server configuration. However, it |
| can be told to listen to more than one port, to listen to only |
| selected addresses, or a combination. This is often combined with the |
| <a href="vhosts/">Virtual Host</a> feature which determines how Apache |
| responds to different IP addresses, hostnames and ports.</p> |
| |
| <p>There are two directives used to restrict or specify which addresses |
| and ports Apache listens to. The <code>BindAddress</code> directive |
| is used to restrict the server to listening to a single IP address. |
| The <code>Listen</code> directive can be used to specify multiple |
| IP addresses and/or Ports to which Apache will listen.</p> |
| |
| <p>The <code>ListenBackLog</code>, <code>SendBufferSize</code>, and |
| <code>TimeOut</code> directives are used to adjust how Apache |
| interacts with the network.</p> |
| |
| <p>The <code>KeepAlive</code>, <code>KeepAliveTimeout</code>, |
| and <code>MaxKeepAliveRequests</code> directives are used to |
| configure how Apache handles persistent connections.</p> |
| |
| <hr> |
| <h2><a name="resource">Limiting Resource Usage</a></h2> |
| <table border="1"> |
| <tr><td valign="top"> |
| <strong>Related Directives</strong><br><br> |
| |
| <a href="mod/core.html#limitrequestbody">LimitRequestBody</a><br> |
| <a href="mod/core.html#limitrequestfields">LimitRequestFields</a><br> |
| <a href="mod/core.html#limitrequestfieldsize">LimitRequestFieldsize</a><br> |
| <a href="mod/core.html#limitrequestline">LimitRequestLine</a><br> |
| <a href="mod/core.html#rlimitcpu">RLimitCPU</a><br> |
| <a href="mod/core.html#rlimitmem">RLimitMEM</a><br> |
| <a href="mod/core.html#rlimitnproc">RLimitNPROC</a><br> |
| <a href="mod/core.html#threadstacksize">ThreadStackSize</a><br> |
| </td></tr></table> |
| |
| <p>The <code>Limit</code>* directives are used to place limits |
| on the amount of resources Apache will use in reading requests |
| from clients. By limiting these values, some kinds of denial |
| of service attacks can be mitigated.</p> |
| |
| <p>The <code>RLimit</code>* directives are used to limit the amount |
| of resources which can be used by processes forked off from |
| the Apache children. In particular, this will control |
| resources used by CGI scripts and SSI exec commands.</p> |
| |
| <p>The <code>ThreadStackSize</code> directive is used only |
| on Netware to control the stock size.</p> |
| |
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