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566 lines
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566 lines
30 KiB
Plaintext
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--><title>Log Files- Apache HTTP Server</title><link href="./style/manual.css" type="text/css" rel="stylesheet"/></head><body><blockquote><div align="center"><img src="./images/sub.gif" alt="[APACHE DOCUMENTATION]"/><h3>Apache HTTP Server Version 2.0</h3></div><h1 align="center">Log Files</h1>
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<p>In order to effectively manage a web server, it is necessary
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to get feedback about the activity and performance of the
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server as well as any problems that may be occuring. The Apache
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HTTP Server provides very comprehensive and flexible logging
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capabilities. This document describes how to configure its
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logging capabilities, and how to understand what the logs
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contain.</p>
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<ul><li><a href="#security">Security Warning</a></li><li><a href="#errorlog">Error Log</a></li><li><a href="#accesslog">Access Log</a><ul><li><a href="#common">Common Log Format</a></li><li><a href="#combined">Combined Log Format</a></li><li><a href="#multiple">Multiple Access Logs</a></li><li><a href="#conditional">Conditional Logs</a></li></ul></li><li><a href="#rotation">Rotation Logs</a></li><li><a href="#piped">Piped Logs</a></li><li><a href="#virtualhost">Virtual Hosts</a></li><li><a href="#other">Other Log Files</a><ul><li><a href="#pidfile">PID File</a></li><li><a href="#scriptlog">Script Log</a></li><li><a href="#rewritelog">Rewrite Log</a></li></ul></li></ul><hr/><h2><a name="security">Security Warning</a></h2>
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<p>Anyone who can write to the directory where Apache is
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writing a log file can almost certainly gain access to the uid
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that the server is started as, which is normally root. Do
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<em>NOT</em> give people write access to the directory the logs
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are stored in without being aware of the consequences; see the
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<a href="misc/security_tips.html">security tips</a> document
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for details.</p>
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<p>In addition, log files may contain information supplied
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directly by the client, without escaping. Therefore, it is
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possible for malicious clients to insert control-characters in
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the log files, so care must be taken in dealing with raw
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logs.</p>
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<h2><a name="errorlog">Error Log</a></h2>
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<table border="1"><tr><td valign="top"><strong>Related Modules</strong><br/><br/></td><td valign="top"><strong>Related Directives</strong><br/><br/><a href="./mod/mod_core.html#errorlog" class="directive"><code class="directive">ErrorLog</code></a><br/><a href="./mod/mod_core.html#loglevel" class="directive"><code class="directive">LogLevel</code></a><br/></td></tr></table>
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<p>The server error log, whose name and location is set by the
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<a href="./mod/core.html#errorlog" class="directive"><code class="directive">ErrorLog</code></a> directive, is the
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most important log file. This is the place where Apache httpd
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will send diagnostic information and record any errors that it
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encounters in processing requests. It is the first place to
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look when a problem occurs with starting the server or with the
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operation of the server, since it will often contain details of
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what went wrong and how to fix it.</p>
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<p>The error log is usually written to a file (typically
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<code>error_log</code> on unix systems and
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<code>error.log</code> on Windows and OS/2). On unix systems it
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is also possible to have the server send errors to
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<code>syslog</code> or <a href="#piped">pipe them to a
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program</a>.</p>
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<p>The format of the error log is relatively free-form and
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descriptive. But there is certain information that is contained
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in most error log entries. For example, here is a typical
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message.</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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[Wed Oct 11 14:32:52 2000] [error] [client 127.0.0.1]
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client denied by server configuration:
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/export/home/live/ap/htdocs/test
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</code></td></tr></table></blockquote>
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<p>The first item in the log entry is the date and time of the
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message. The second entry lists the severity of the error being
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reported. The <a href="./mod/core.html#loglevel" class="directive"><code class="directive">LogLevel</code></a>
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directive is used to control the types of errors that are sent
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to the error log by restricting the severity level. The third
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entry gives the IP address of the client that generated the
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error. Beyond that is the message itself, which in this case
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indicates that the server has been configured to deny the
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client access. The server reports the file-system path (as
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opposed to the web path) of the requested document.</p>
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<p>A very wide variety of different messages can appear in the
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error log. Most look similar to the example above. The error
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log will also contain debugging output from CGI scripts. Any
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information written to <code>stderr</code> by a CGI script will
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be copied directly to the error log.</p>
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<p>It is not possible to customize the error log by adding or
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removing information. However, error log entries dealing with
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particular requests have corresponding entries in the <a href="#accesslog">access log</a>. For example, the above example
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entry corresponds to an access log entry with status code 403.
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Since it is possible to customize the access log, you can
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obtain more information about error conditions using that log
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file.</p>
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<p>During testing, it is often useful to continuously monitor
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the error log for any problems. On unix systems, you can
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accomplish this using:</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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tail -f error_log
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</code></td></tr></table></blockquote>
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<h2><a name="accesslog">Access Log</a></h2>
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<table border="1"><tr><td valign="top"><strong>Related Modules</strong><br/><br/><code><a href="./mod/mod_log_config.html">mod_log_config</a></code>, <br/><code><a href="./mod/mod_setenvif.html">mod_setenvif</a></code><br/></td><td valign="top"><strong>Related Directives</strong><br/><br/><a href="./mod/mod_log_config.html#customlog" class="directive"><code class="directive">CustomLog</code></a><br/><a href="./mod/mod_log_config.html#logformat" class="directive"><code class="directive">LogFormat</code></a><br/><a href="./mod/mod_setenvif.html#setenvif" class="directive"><code class="directive">SetEnvIf</code></a><br/></td></tr></table>
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<p>The server access log records all requests processed by the
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server. The location and content of the access log are
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controlled by the <a href="./mod/mod_log_config.html#
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customlog" class="directive"><code class="directive">
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CustomLog</code></a> directive. The <a href="./mod/mod_log_config.html#
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logformat" class="directive"><code class="directive">
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LogFormat</code></a> directive can be used to simplify the selection of
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the contents of the logs. This section describes how to configure the server
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to record information in the access log.</p>
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<p>Of course, storing the information in the access log is only
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the start of log management. The next step is to analyze this
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information to produce useful statistics. Log analysis in
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general is beyond the scope of this document, and not really
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part of the job of the web server itself. For more information
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about this topic, and for applications which perform log
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analysis, check the <a href="http://dmoz.org/Computers/Software/Internet/Site_Management/Log_analysis/">
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Open Directory</a> or <a href="http://dir.yahoo.com/Computers_and_Internet/Software/Internet/World_Wide_Web/Servers/Log_Analysis_Tools/">
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Yahoo</a>.</p>
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<p>Various versions of Apache httpd have used other modules and
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directives to control access logging, including
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mod_log_referer, mod_log_agent, and the
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<code>TransferLog</code> directive. The <code>CustomLog</code>
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directive now subsumes the functionality of all the older
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directives.</p>
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<p>The format of the access log is highly configurable. The
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format is specified using a <a href="./mod/mod_log_config.html#
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customlog" class="directive"><code class="directive">
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CustomLog</code></a> that
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looks much like a C-style printf(1) format string. Some
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examples are presented in the next sections. For a complete
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list of the possible contents of the format string, see the <a href="mod/mod_log_config.html">mod_log_config
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documentation</a>.</p>
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<h3><a name="common">Common Log Format</a></h3>
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<p>A typical configuration for the access log might look as
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follows.</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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LogFormat "%h %l %u %t \"%r\" %>s %b" common<br>
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CustomLog logs/access_log common
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</code></td></tr></table></blockquote>
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<p>This defines the <em>nickname</em> <code>common</code> and
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associates it with a particular log format string. The format
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string consists of percent directives, each of which tell the
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server to log a particular piece of information. Literal
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characters may also be placed in the format string and will be
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copied directly into the log output. The quote character
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(<code>"</code>) must be escaped by placing a back-slash before
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it to prevent it from being interpreted as the end of the
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format string. The format string may also contain the special
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control characters "<code>\n</code>" for new-line and
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"<code>\t</code>" for tab.</p>
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<p>The <code>CustomLog</code> directive sets up a new log file
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using the defined <em>nickname</em>. The filename for the
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access log is relative to the <a href="./mod/core.html#
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serverroot" class="directive"><code class="directive">
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ServerRoot</code></a> unless it begins
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with a slash.</p>
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<p>The above configuration will write log entries in a format
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known as the Common Log Format (CLF). This standard format can
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be produced by many different web servers and read by many log
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analysis programs. The log file entries produced in CLF will
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look something like this:</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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127.0.0.1 - frank [10/Oct/2000:13:55:36 -0700] "GET
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/apache_pb.gif HTTP/1.0" 200 2326
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</code></td></tr></table></blockquote>
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<p>Each part of this log entry is described below.</p>
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<dl>
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<dt><code>127.0.0.1</code> (<code>%h</code>)</dt>
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<dd>This is the IP address of the client (remote host) which
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made the request to the server. If <a href="./mod/core.html#
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hostnamelookups" class="directive"><code class="directive">
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HostnameLookups</code></a> is
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set to <code>On</code>, then the server will try to determine
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the hostname and log it in place of the IP address. However,
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this configuration is not recommended since it can
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significantly slow the server. Instead, it is best to use a
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log post-processor such as <a href="programs/logresolve.html">logresolve</a> to determine
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the hostnames. The IP address reported here is not
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necessarily the address of the machine at which the user is
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sitting. If a proxy server exists between the user and the
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server, this address will be the address of the proxy, rather
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than the originating machine.</dd>
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<dt><code>-</code> (<code>%l</code>)</dt>
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<dd>The "hyphen" in the output indicates that the requested
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piece of information is not available. In this case, the
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information that is not available is the RFC 1413 identity of
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the client determined by <code>identd</code> on the clients
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machine. This information is highly unreliable and should
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almost never be used except on tightly controlled internal
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networks. Apache httpd will not even attempt to determine
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this information unless <a href="./mod/core.html#
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identitycheck" class="directive"><code class="directive">
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IdentityCheck</code></a> is set
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to <code>On</code>.</dd>
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<dt><code>frank</code> (<code>%u</code>)</dt>
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<dd>This is the userid of the person requesting the document
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as determined by HTTP authentication. The same value is
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typically provided to CGI scripts in the
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<code>REMOTE_USER</code> environment variable. If the status
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code for the request (see below) is 401, then this value
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should not be trusted because the user is not yet
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authenticated. If the document is not password protected,
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this entry will be "<code>-</code>" just like the previous
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one.</dd>
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<dt><code>[10/Oct/2000:13:55:36 -0700]</code>
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(<code>%t</code>)</dt>
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<dd>
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The time that the server finished processing the request.
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The format is:
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<blockquote>
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<code>[day/month/year:hour:minute:second zone]<br>
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day = 2*digit<br>
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month = 3*letter<br>
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year = 4*digit<br>
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hour = 2*digit<br>
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minute = 2*digit<br>
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second = 2*digit<br>
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zone = (`+' | `-') 4*digit</code>
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</blockquote>
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It is possible to have the time displayed in another format
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by specifying <code>%{format}t</code> in the log format
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string, where <code>format</code> is as in
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<code>strftime(3)</code> from the C standard library.
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</dd>
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<dt><code>"GET /apache_pb.gif HTTP/1.0"</code>
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(<code>\"%r\"</code>)</dt>
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<dd>The request line from the client is given in double
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quotes. The request line contains a great deal of useful
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information. First, the method used by the client is
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<code>GET</code>. Second, the client requested the resource
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<code>/apache_pb.gif</code>, and third, the client used the
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protocol <code>HTTP/1.0</code>. It is also possible to log
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one or more parts of the request line independently. For
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example, the format string "<code>%m %U%q %H</code>" will log
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the method, path, query-string, and protocol, resulting in
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exactly the same output as "<code>%r</code>".</dd>
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<dt><code>200</code> (<code>%>s</code>)</dt>
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<dd>This is the status code that the server sends back to the
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client. This information is very valuable, because it reveals
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whether the request resulted in a successful response (codes
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beginning in 2), a redirection (codes beginning in 3), an
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error caused by the client (codes beginning in 4), or an
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error in the server (codes beginning in 5). The full list of
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possible status codes can be found in the <a href="http://www.w3.org/Protocols/rfc2616/rfc2616.txt">HTTP
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specification</a> (RFC2616 section 10).</dd>
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<dt><code>2326</code> (<code>%b</code>)</dt>
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<dd>The last entry indicates the size of the object returned
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to the client, not including the response headers. If no
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content was returned to the client, this value will be
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"<code>-</code>". To log "<code>0</code>" for no content, use
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<code>%B</code> instead.</dd>
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</dl>
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<h3><a name="combined">Combined Log Format</a></h3>
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<p>Another commonly used format string is called the Combined
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Log Format. It can be used as follows.</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\"
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\"%{User-agent}i\"" combined<br>
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CustomLog log/acces_log combined
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</code></td></tr></table></blockquote>
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<p>This format is exactly the same as the Common Log Format,
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with the addition of two more fields. Each of the additional
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fields uses the percent-directive
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<code>%{<em>header</em>}i</code>, where <em>header</em> can be
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any HTTP request header. The access log under this format will
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look like:</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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127.0.0.1 - frank [10/Oct/2000:13:55:36 -0700] "GET
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/apache_pb.gif HTTP/1.0" 200 2326
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"http://www.example.com/start.html" "Mozilla/4.08 [en]
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(Win98; I ;Nav)"
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</code></td></tr></table></blockquote>
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<p>The additional fields are:</p>
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<dl>
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<dt><code>"http://www.example.com/start.html"</code>
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(<code>\"%{Referer}i\"</code>)</dt>
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<dd>The "Referer" (sic) HTTP request header. This gives the
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site that the client reports having been referred from. (This
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should be the page that links to or includes
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<code>/apache_pb.gif</code>).</dd>
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<dt><code>"Mozilla/4.08 [en] (Win98; I ;Nav)"</code>
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(<code>\"%{User-agent}i\"</code>)</dt>
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<dd>The User-Agent HTTP request header. This is the
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identifying information that the client browser reports about
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itself.</dd>
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</dl>
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<h3><a name="multiple">Multiple Access Logs</a></h3>
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<p>Multiple access logs can be created simply by specifying
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multiple <a href="./mod/core.html#customlog" class="directive"><code class="directive">CustomLog</code></a>
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directives in the configuration
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file. For example, the following directives will create three
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access logs. The first contains the basic CLF information,
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while the second and third contain referer and browser
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information. The last two <a href="./mod/core.html#
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customlog" class="directive"><code class="directive">
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CustomLog</code></a> lines show how
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to mimic the effects of the <a href="./mod/core.html#referlog" class="directive"><code class="directive">ReferLog</code></a>
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and <a href="./mod/core.html#agentlog" class="directive"><code class="directive">AgentLog</code></a> directives.</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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LogFormat "%h %l %u %t \"%r\" %>s %b" common<br>
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CustomLog logs/access_log common<br>
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CustomLog logs/referer_log "%{Referer}i -> %U"<br>
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CustomLog logs/agent_log "%{User-agent}i"
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</code></td></tr></table></blockquote>
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<p>This example also shows that it is not necessary to define a
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nickname with the <code>LogFormat</code> directive. Instead,
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the log format can be specified directly in the
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<a href="./mod/core.html#customlog" class="directive"><code class="directive">CustomLog</code></a> directive.</p>
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<h3><a name="conditional">Conditional Logs</a></h3>
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|
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<p>There are times when it is convenient to exclude certain
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entries from the access logs based on characteristics of the
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client request. This is easily accomplished with the help of <a href="env.html">environment variables</a>. First, an
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environment variable must be set to indicate that the request
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|
meets certain conditions. This is usually accomplished with
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<a href="./mod/mod_setenvif.html#setenvif" class="directive"><code class="directive">SetEnvIf</code></a>. Then the
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<code>env=</code> clause of the <code>CustomLog</code>
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directive is used to include or exclude requests where the
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environment variable is set. Some examples:</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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# Mark requests from the loop-back interface<br>
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SetEnvIf Remote_Addr "127\.0\.0\.1" dontlog<br>
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# Mark requests for the robots.txt file<br>
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SetEnvIf Request_URI "^/robots\.txt$" dontlog<br>
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# Log what remains<br>
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CustomLog logs/access_log common env=!dontlog
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</code></td></tr></table></blockquote>
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<p>As another example, consider logging requests from
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english-speakers to one log file, and non-english speakers to a
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different log file.</p>
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<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
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SetEnvIf Accept-Language "en" english<br>
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CustomLog logs/english_log common env=english<br>
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CustomLog logs/non_english_log common env=!english
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</code></td></tr></table></blockquote>
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|
|
<p>Although we have just shown that conditional logging is very
|
|
powerful and flexibly, it is not the only way to control the
|
|
contents of the logs. Log files are more useful when they
|
|
contain a complete record of server activity. It is often
|
|
easier to simply post-process the log files to remove requests
|
|
that you do not want to consider.</p>
|
|
|
|
<h2><a name="rotation">Rotation Logs</a></h2>
|
|
|
|
|
|
<p>On even a moderately busy server, the quantity of
|
|
information stored in the log files is very large. The access
|
|
log file typically grows 1 MB or more per 10,000 requests. It
|
|
will consequently be necessary to periodically rotate the log
|
|
files by moving or deleting the existing logs. This cannot be
|
|
done while the server is running, because Apache will continue
|
|
writing to the old log file as long as it holds the file open.
|
|
Instead, the server must be <a href="stopping.html">restarted</a> after the log files are
|
|
moved or deleted so that it will open new log files.</p>
|
|
|
|
<p>By using a <em>graceful</em> restart, the server can be
|
|
instructed to open new log files without losing any existing or
|
|
pending connections from clients. However, in order to
|
|
accomplish this, the server must continue to write to the old
|
|
log files while it finishes serving old requests. It is
|
|
therefore necessary to wait for some time after the restart
|
|
before doing any processing on the log files. A typical
|
|
scenario that simply rotates the logs and compresses the old
|
|
logs to save space is:</p>
|
|
|
|
<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
|
|
mv access_log access_log.old<br>
|
|
mv error_log error_log.old<br>
|
|
apachectl graceful<br>
|
|
sleep 600<br>
|
|
gzip access_log.old error_log.old
|
|
</code></td></tr></table></blockquote>
|
|
|
|
<p>Another way to perform log rotation is using <a href="#piped">piped logs</a> as discussed in the next
|
|
section.</p>
|
|
<h2><a name="piped">Piped Logs</a></h2>
|
|
|
|
|
|
<p>Apache httpd is capable of writing error and access log
|
|
files through a pipe to another process, rather than directly
|
|
to a file. This capability dramatically increases the
|
|
flexibility of logging, without adding code to the main server.
|
|
In order to write logs to a pipe, simply replace the filename
|
|
with the pipe character "<code>|</code>", followed by the name
|
|
of the executable which should accept log entries on its
|
|
standard input. Apache will start the piped-log process when
|
|
the server starts, and will restart it if it crashes while the
|
|
server is running. (This last feature is why we can refer to
|
|
this technique as "reliable piped logging".)</p>
|
|
|
|
<p>Piped log processes are spawned by the parent Apache httpd
|
|
process, and inherit the userid of that process. This means
|
|
that piped log programs usually run as root. It is therefore
|
|
very important to keep the programs simple and secure.</p>
|
|
|
|
<p>Some simple examples using piped logs:</p>
|
|
|
|
<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
|
|
# compressed logs<br>
|
|
CustomLog "|/usr/bin/gzip -c >>
|
|
/var/log/access_log.gz" common<br>
|
|
# almost-real-time name resolution<br>
|
|
CustomLog "|/usr/local/apache/bin/logresolve >>
|
|
/var/log/access_log" common
|
|
</code></td></tr></table></blockquote>
|
|
|
|
<p>Notice that quotes are used to enclose the entire command
|
|
that will be called for the pipe. Although these examples are
|
|
for the access log, the same technique can be used for the
|
|
error log.</p>
|
|
|
|
<p>One important use of piped logs is to allow log rotation
|
|
without having to restart the server. The Apache HTTP Server
|
|
includes a simple program called <a href="programs/rotatelogs.html">rotatelogs</a> for this
|
|
purpose. For example, to rotate the logs every 24 hours, you
|
|
can use:</p>
|
|
|
|
<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
|
|
CustomLog "|/usr/local/apache/bin/rotatelogs
|
|
/var/log/access_log 86400" common
|
|
</code></td></tr></table></blockquote>
|
|
|
|
<p>A similar, but much more flexible log rotation program
|
|
called <a href="http://www.cronolog.org/">cronolog</a>
|
|
is available at an external site.</p>
|
|
|
|
<p>As with conditional logging, piped logs are a very powerful
|
|
tool, but they should not be used where a simpler solution like
|
|
off-line post-processing is available.</p>
|
|
<h2><a name="virtualhost">Virtual Hosts</a></h2>
|
|
|
|
|
|
<p>When running a server with many <a href="vhosts/">virtual
|
|
hosts</a>, there are several options for dealing with log
|
|
files. First, it is possible to use logs exactly as in a
|
|
single-host server. Simply by placing the logging directives
|
|
outside the <code><VirtualHost></code> sections in the
|
|
main server context, it is possible to log all requests in the
|
|
same access log and error log. This technique does not allow
|
|
for easy collection of statistics on individual virtual
|
|
hosts.</p>
|
|
|
|
<p>If <a href="./mod/mod_log_config.html#customlog" class="directive"><code class="directive">CustomLog</code></a>
|
|
or <a href="./mod/mod_log_config.html#errorlog" class="directive"><code class="directive">ErrorLog</code></a>
|
|
directives are placed inside a <a href="./mod/core.html#
|
|
<virtualhost>" class="directive"><code class="directive">
|
|
<VirtualHost></code></a>
|
|
section, all requests or errors for that virtual host will be
|
|
logged only to the specified file. Any virtual host which does
|
|
not have logging directives will still have its requests sent
|
|
to the main server logs. This technique is very useful for a
|
|
small number of virtual hosts, but if the number of hosts is
|
|
very large, it can be complicated to manage. In addition, it
|
|
can often create problems with <a href="vhosts/fd-limits.html">insufficient file
|
|
descriptors</a>.</p>
|
|
|
|
<p>For the access log, there is a very good compromise. By
|
|
adding information on the virtual host to the log format
|
|
string, it is possible to log all hosts to the same log, and
|
|
later split the log into individual files. For example,
|
|
consider the following directives.</p>
|
|
|
|
<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
|
|
LogFormat "%v %l %u %t \"%r\" %>s %b"
|
|
comonvhost<br>
|
|
CustomLog logs/access_log comonvhost
|
|
</code></td></tr></table></blockquote>
|
|
|
|
<p>The <code>%v</code> is used to log the name of the virtual
|
|
host that is serving the request. Then a program like <a href="programs/other.html">split-logfile</a> can be used to
|
|
post-process the access log in order to split it into one file
|
|
per virtual host.</p>
|
|
<h2><a name="other">Other Log Files</a></h2>
|
|
|
|
|
|
<table border="1"><tr><td valign="top"><strong>Related Modules</strong><br/><br/><code><a href="./mod/mod_cgi.html">mod_cgi</a></code>, <br/><code><a href="./mod/mod_rewrite.html">mod_rewrite</a></code><br/></td><td valign="top"><strong>Related Directives</strong><br/><br/><a href="./mod/core.html#pidfile" class="directive"><code class="directive">PidFile</code></a><br/><a href="./mod/mod_rewrite.html#rewritelog" class="directive"><code class="directive">RewriteLog</code></a><br/><a href="./mod/mod_rewrite.html#rewriteloglevel" class="directive"><code class="directive">RewriteLogLevel</code></a><br/><a href="./mod/mod_cgi.html#scriptlog" class="directive"><code class="directive">ScriptLog</code></a><br/><a href="./mod/mod_cgi.html#scriptloglength" class="directive"><code class="directive">ScriptLogLength</code></a><br/><a href="./mod/mod_cgi.html#scriptbuffer" class="directive"><code class="directive">ScriptBuffer</code></a><br/></td></tr></table>
|
|
|
|
<h3><a name="pidfile">PID File</a></h3>
|
|
|
|
|
|
<p>On startup, Apache httpd saves the process id of the parent
|
|
httpd process to the file <code>logs/httpd.pid</code>. This
|
|
filename can be changed with the <a href="./mod/core.html#pidfile
|
|
" class="directive"><code class="directive">PidFile
|
|
</code></a> directive. The
|
|
process-id is for use by the administrator in restarting and
|
|
terminating the daemon by sending signals to the parent
|
|
process; on Windows, use the -k command line option instead.
|
|
For more information see the <a href="stopping.html">Stopping
|
|
and Restarting</a> page.</p>
|
|
|
|
|
|
<h3><a name="scriptlog">Script Log</a></h3>
|
|
|
|
|
|
<p>In order to aid in debugging, the <a href="./mod/mod_cgi.html#
|
|
scriptlog" class="directive"><code class="directive">
|
|
ScriptLog</code></a> directive
|
|
allows you to record the input to and output from CGI scripts.
|
|
This should only be used in testing - not for live servers.
|
|
More information is available in the <a href="mod/mod_cgi.html">mod_cgi documentation</a>.</p>
|
|
|
|
|
|
<h3><a name="rewritelog">Rewrite Log</a></h3>
|
|
|
|
|
|
<p>When using the powerful and complex features of <a href="mod/mod_rewrite.html">mod_rewrite</a>, it is almost
|
|
always necessary to use the <a href="./mod/mod_rewrite.html#
|
|
rewritelog" class="directive"><code class="directive">
|
|
RewriteLog</code></a> to help
|
|
in debugging. This log file produces a detailed analysis of how
|
|
the rewriting engine transforms requests. The level of detail
|
|
is controlled by the <a href="./mod/mod_rewrite.html#
|
|
rewriteloglevel" class="directive"><code class="directive">
|
|
RewriteLogLevel</code></a> directive.</p>
|
|
|
|
</blockquote><hr/><h3 align="center">Apache HTTP Server Version 2.0</h3><a href="./"><img src="./images/index.gif" alt="Index"/></a><a href="./"><img src="./images/home.gif" alt="Home"/></a></body></html> |