| [66] | 1 | <html><head><META http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><title>Apache Tomcat 6.0 - Apache Portable Runtime (APR) based Native library for Tomcat</title><meta value="Remy Maucherat" name="author"><meta value="" name="email"></head><body vlink="#525D76" alink="#525D76" link="#525D76" text="#000000" bgcolor="#ffffff"><table cellspacing="0" width="100%" border="0"><!--PAGE HEADER--><tr><td><!--PROJECT LOGO--><a href="http://tomcat.apache.org/"><img border="0" alt=" |
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| 2 | The Apache Tomcat Servlet/JSP Container |
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| 3 | " align="right" src="./../images/tomcat.gif"></a></td><td><font face="arial,helvetica,sanserif"><h1>Apache Tomcat 6.0</h1></font></td><td><!--APACHE LOGO--><a href="http://www.apache.org/"><img border="0" alt="Apache Logo" align="right" src="./../images/asf-logo.gif"></a></td></tr></table><table cellspacing="4" width="100%" border="0"><!--HEADER SEPARATOR--><tr><td colspan="2"><hr size="1" noshade></td></tr><tr><!--RIGHT SIDE MAIN BODY--><td align="left" valign="top" width="80%"><table cellspacing="4" width="100%" border="0"><tr><td valign="top" align="left"><h1>Apache Tomcat 6.0</h1><h2>Apache Portable Runtime (APR) based Native library for Tomcat</h2></td><td nowrap="true" valign="top" align="right"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Introduction"><strong>Introduction</strong></a></font></td></tr><tr><td><blockquote> |
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| 4 | |
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| 5 | <p> |
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| 6 | Tomcat can use the <a href="http://apr.apache.org/">Apache Portable Runtime</a> to |
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| 7 | provide superior scalability, performance, and better integration with native server |
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| 8 | technologies. The Apache Portable Runtime is a highly portable library that is at |
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| 9 | the heart of Apache HTTP Server 2.x. APR has many uses, including access to advanced IO |
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| 10 | functionality (such as sendfile, epoll and OpenSSL), OS level functionality (random number |
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| 11 | generation, system status, etc), and native process handling (shared memory, NT |
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| 12 | pipes and Unix sockets). |
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| 13 | </p> |
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| 14 | |
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| 15 | <p> |
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| 16 | These features allows making Tomcat a general purpose webserver, will enable much better |
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| 17 | integration with other native web technologies, and overall make Java much more viable as |
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| 18 | a full fledged webserver platform rather than simply a backend focused technology. |
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| 19 | </p> |
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| 20 | |
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| 21 | </blockquote></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Installation"><strong>Installation</strong></a></font></td></tr><tr><td><blockquote> |
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| 22 | |
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| 23 | <p> |
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| 24 | APR support requires three main native components to be installed: |
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| 25 | <ul> |
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| 26 | <li>APR library</li> |
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| 27 | <li>JNI wrappers for APR used by Tomcat (libtcnative)</li> |
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| 28 | <li>OpenSSL libraries</li> |
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| 29 | </ul> |
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| 30 | </p> |
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| 31 | |
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| 32 | <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Windows"><strong>Windows</strong></a></font></td></tr><tr><td><blockquote> |
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| 33 | |
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| 34 | <p> |
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| 35 | Windows binaries are provided for tcnative-1, which is a statically compiled .dll which includes |
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| 36 | OpenSSL and APR. It can be downloaded from <a href="http://tomcat.heanet.ie/native/">here</a> |
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| 37 | as 32bit or AMD x86-64 binaries. |
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| 38 | In security conscious production environments, it is recommended to use separate shared dlls |
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| 39 | for OpenSSL, APR, and libtcnative-1, and update them as needed according to security bulletins. |
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| 40 | Windows OpenSSL binaries are linked from the <a href="http://www.openssl.org">Official OpenSSL |
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| 41 | website</a> (see related/binaries). |
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| 42 | </p> |
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| 43 | |
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| 44 | </blockquote></td></tr></table> |
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| 45 | |
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| 46 | <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Linux"><strong>Linux</strong></a></font></td></tr><tr><td><blockquote> |
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| 47 | |
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| 48 | <p> |
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| 49 | Most Linux distributions will ship packages for APR and OpenSSL. The JNI wrapper (libtcnative) will |
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| 50 | then have to be compiled. It depends on APR, OpenSSL, and the Java headers. |
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| 51 | </p> |
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| 52 | |
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| 53 | <p> |
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| 54 | Requirements: |
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| 55 | <ul> |
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| 56 | <li>APR 1.2+ development headers (libapr1-dev package)</li> |
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| 57 | <li>OpenSSL 0.9.7+ development headers (libssl-dev package)</li> |
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| 58 | <li>JNI headers from Java compatible JDK 1.4+</li> |
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| 59 | <li>GNU development environment (gcc, make)</li> |
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| 60 | </ul> |
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| 61 | </p> |
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| 62 | |
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| 63 | <p> |
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| 64 | The wrapper library sources are located in the Tomcat binary bundle, in the |
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| 65 | <code>bin/tomcat-native.tar.gz</code> archive. |
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| 66 | Once the build environment is installed and the source archive is extracted, the wrapper library |
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| 67 | can be compiled using (from the folder containing the configure script): |
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| 68 | <div align="left"><table border="0" cellpadding="0" cellspacing="4"><tr><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr><tr><td width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#ffffff"><pre>./configure && make && make install</pre></td><td width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr><tr><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr></table></div> |
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| 69 | </p> |
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| 70 | |
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| 71 | </blockquote></td></tr></table> |
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| 72 | |
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| 73 | </blockquote></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="APR Components"><strong>APR Components</strong></a></font></td></tr><tr><td><blockquote> |
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| 74 | |
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| 75 | <p> |
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| 76 | Once the libraries are properly installed and available to Java (if loading fails, the library path |
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| 77 | will be displayed), the Tomcat connectors will automatically use APR. Configuration of the connectors |
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| 78 | is similar to the regular connectors, but have a few extra attributes which are used to configure |
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| 79 | APR components. Note that the defaults should be well tuned for most use cases, and additional |
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| 80 | tweaking shouldn't be required. |
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| 81 | </p> |
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| 82 | |
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| 83 | <p> |
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| 84 | When APR is enabled, the following features are also enabled in Tomcat: |
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| 85 | <ul> |
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| 86 | <li>Secure session ID generation by default on all platforms (platforms other than Linux required |
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| 87 | random number generation using a configured entropy)</li> |
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| 88 | <li>OS level statistics on memory usage and CPU usage by the Tomcat process are displayed by |
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| 89 | the status servlet</li> |
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| 90 | </ul> |
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| 91 | </p> |
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| 92 | |
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| 93 | </blockquote></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="APR Lifecycle Listener Configuration"><strong>APR Lifecycle Listener Configuration</strong></a></font></td></tr><tr><td><blockquote> |
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| 94 | <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="AprLifecycleListener"><strong>AprLifecycleListener</strong></a></font></td></tr><tr><td><blockquote> |
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| 95 | <attribute name="SSLEngine" required="false"> |
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| 96 | <p> |
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| 97 | Name of the SSLEngine to use. off: Do not use SSL, on: Use SSL but no specific ENGINE. |
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| 98 | The default value is <b>on</b>. |
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| 99 | This initializes the native SSL engine, then enable the use of this engine in the connector |
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| 100 | using the <code>SSLEnabled</code> attribute. Example: |
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| 101 | <div align="left"><table border="0" cellpadding="0" cellspacing="4"><tr><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr><tr><td width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#ffffff"><pre> |
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| 102 | <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" /> |
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| 103 | </pre></td><td width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr><tr><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr></table></div> |
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| 104 | </p> |
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| 105 | <p>See the <a href="http://www.openssl.org">Official OpenSSL |
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| 106 | website</a> for more details on SSL hardware engines and manufacturers. |
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| 107 | </p> |
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| 108 | </attribute> |
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| 109 | </blockquote></td></tr></table> |
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| 110 | </blockquote></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="APR Connectors Configuration"><strong>APR Connectors Configuration</strong></a></font></td></tr><tr><td><blockquote> |
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| 111 | |
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| 112 | <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="HTTP"><strong>HTTP</strong></a></font></td></tr><tr><td><blockquote> |
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| 113 | |
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| 114 | <p> |
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| 115 | When APR is enabled, the HTTP connector will use sendfile for hadling large static files (all such |
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| 116 | files will be sent ansychronously using high performance kernel level calls), and will use |
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| 117 | a socket poller for keepalive, increasing scalability of the server. |
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| 118 | </p> |
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| 119 | |
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| 120 | <p> |
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| 121 | The following attributes are supported in the HTTP APR connector in addition to the ones supported |
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| 122 | in the regular HTTP connector: |
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| 123 | </p> |
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| 124 | |
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| 125 | <table cellpadding="5" border="1"><tr><th bgcolor="#023264" width="15%"><font color="#ffffff">Attribute</font></th><th bgcolor="#023264" width="85%"><font color="#ffffff">Description</font></th></tr><tr><td valign="center" align="left"><code>keepAliveTimeout</code></td><td valign="center" align="left"> |
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| 126 | <p>The number of milliseconds this <strong>Connector</strong> will wait for |
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| 127 | another HTTP request before closing the connection. |
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| 128 | The default value is to use the value that has been set for the |
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| 129 | connectionTimeout attribute. This value also controls the timeout interval which |
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| 130 | is used for Comet connections.</p> |
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| 131 | </td></tr><tr><td valign="center" align="left"><code>pollTime</code></td><td valign="center" align="left"> |
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| 132 | <p>Duration of a poll call. Lowering this value will slightly decrease latency of connections |
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| 133 | being kept alive in some cases, but will use more CPU as more poll calls are being made. The |
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| 134 | default value is 2000 (5ms).</p> |
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| 135 | </td></tr><tr><td valign="center" align="left"><code>pollerSize</code></td><td valign="center" align="left"> |
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| 136 | <p>Amount of sockets that the poller responsible for polling kept alive connections can hold at a |
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| 137 | given time. Extra connections will be closed right away. The default value is 8192, corresponding to |
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| 138 | 8192 keepalive connections.</p> |
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| 139 | </td></tr><tr><td valign="center" align="left"><code>useSendfile</code></td><td valign="center" align="left"> |
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| 140 | <p>Use kernel level sendfile for certain static files. The default value is true.</p> |
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| 141 | </td></tr><tr><td valign="center" align="left"><code>sendfileSize</code></td><td valign="center" align="left"> |
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| 142 | <p>Amount of sockets that the poller responsible for sending static files asynchronously can hold |
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| 143 | at a given time. Extra connections will be closed right away without any data being sent |
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| 144 | (resulting in a zero length file on the client side). Note that in most cases, sendfile is a call |
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| 145 | that will return right away (being taken care of "synchonously" by the kernel), and the sendfile |
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| 146 | poller will not be used, so the amount of static files which can be sent concurrently is much larger |
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| 147 | than the specified amount. The default value is 1024.</p> |
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| 148 | </td></tr></table> |
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| 149 | |
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| 150 | </blockquote></td></tr></table> |
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| 151 | |
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| 152 | <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="HTTPS"><strong>HTTPS</strong></a></font></td></tr><tr><td><blockquote> |
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| 153 | |
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| 154 | <p> |
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| 155 | When APR is enabled, the HTTPS connector will use a socket poller for keepalive, increasing |
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| 156 | scalability of the server. It also uses OpenSSL, which may be more optimized than JSSE depending |
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| 157 | on the processor being used, and can be complemented with many commercial accelerator components. |
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| 158 | Unlike the HTTP connector, the HTTPS connector cannot use sendfile to optimize static file |
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| 159 | processing. |
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| 160 | </p> |
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| 161 | |
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| 162 | <p> |
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| 163 | The HTTPS APR connector has the same basic attributes than the HTTP APR connector, but adds |
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| 164 | OpenSSL specific ones. For the full details on using OpenSSL, please refer to OpenSSL documentations |
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| 165 | and the many books available for it (see the <a href="http://www.openssl.org">Official OpenSSL |
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| 166 | website</a>). The SSL specific attributes for the connector are: |
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| 167 | </p> |
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| 168 | |
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| 169 | <table cellpadding="5" border="1"><tr><th bgcolor="#023264" width="15%"><font color="#ffffff">Attribute</font></th><th bgcolor="#023264" width="85%"><font color="#ffffff">Description</font></th></tr><tr><td valign="center" align="left"><code>SSLEnabled</code></td><td valign="center" align="left"> |
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| 170 | <p> |
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| 171 | Enable SSL on the socket, default value is false. Set this value to true |
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| 172 | to enable SSL handshake/encryption/decryption in the APR connector. |
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| 173 | </p> |
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| 174 | </td></tr><tr><td valign="center" align="left"><code>SSLProtocol</code></td><td valign="center" align="left"> |
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| 175 | <p> |
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| 176 | Protocol which may be used for communicating with clients. The default is "all", with |
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| 177 | other acceptable values being "SSLv2", "SSLv3", "TLSv1", and "SSLv2+SSLv3". |
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| 178 | </p> |
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| 179 | </td></tr><tr><td valign="center" align="left"><code>SSLCipherSuite</code></td><td valign="center" align="left"> |
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| 180 | <p> |
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| 181 | Ciphers which may be used for communicating with clients. The default is "ALL", with |
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| 182 | other acceptable values being a list of ciphers, with ":" used as the delimiter |
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| 183 | (see OpenSSL documentation for the list of ciphers supported). |
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| 184 | </p> |
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| 185 | </td></tr><tr><td valign="center" align="left"><strong><code>SSLCertificateFile</code></strong></td><td valign="center" align="left"> |
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| 186 | <p> |
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| 187 | Name of the file that contains the server certificate. The format is PEM-encoded. |
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| 188 | </p> |
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| 189 | </td></tr><tr><td valign="center" align="left"><code>SSLCertificateKeyFile</code></td><td valign="center" align="left"> |
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| 190 | <p> |
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| 191 | Name of the file that contains the server private key. The format is PEM-encoded. |
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| 192 | The default value is the value of "SSLCertificateFile" and in this case both certificate |
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| 193 | and private key have to be in this file (NOT RECOMMENDED). |
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| 194 | </p> |
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| 195 | </td></tr><tr><td valign="center" align="left"><code>SSLPassword</code></td><td valign="center" align="left"> |
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| 196 | <p> |
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| 197 | Pass phrase for the encrypted private key. If "SSLPassword" is not provided, the callback fonction |
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| 198 | should prompt for the pass phrase. |
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| 199 | </p> |
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| 200 | </td></tr><tr><td valign="center" align="left"><code>SSLVerifyClient</code></td><td valign="center" align="left"> |
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| 201 | <p> |
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| 202 | Ask client for certificate. The default is "none", meaning the client will not have the opportunity |
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| 203 | to submit a certificate. Other acceptable values include "optional", "require" and "optionalNoCA". |
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| 204 | </p> |
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| 205 | </td></tr><tr><td valign="center" align="left"><code>SSLVerifyDepth</code></td><td valign="center" align="left"> |
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| 206 | <p> |
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| 207 | Maximum verification depth for client certificates. The default is "10". |
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| 208 | </p> |
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| 209 | </td></tr><tr><td valign="center" align="left"><code>SSLCACertificateFile</code></td><td valign="center" align="left"> |
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| 210 | <p> |
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| 211 | See <a href="http://httpd.apache.org/docs/2.2/mod/mod_ssl.html#sslcacertificatefile">the mod_ssl documentation</a>. |
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| 212 | </p> |
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| 213 | </td></tr><tr><td valign="center" align="left"><code>SSLCACertificatePath</code></td><td valign="center" align="left"> |
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| 214 | <p> |
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| 215 | See <a href="http://httpd.apache.org/docs/2.2/mod/mod_ssl.html#sslcacertificatepath">the mod_ssl documentation</a>. |
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| 216 | </p> |
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| 217 | </td></tr><tr><td valign="center" align="left"><code>SSLCertificateChainFile</code></td><td valign="center" align="left"> |
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| 218 | <p> |
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| 219 | See <a href="http://httpd.apache.org/docs/2.2/mod/mod_ssl.html#sslcertificatechainfile">the mod_ssl documentation</a>. |
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| 220 | </p> |
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| 221 | </td></tr><tr><td valign="center" align="left"><code>SSLCARevocationFile</code></td><td valign="center" align="left"> |
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| 222 | <p> |
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| 223 | See <a href="http://httpd.apache.org/docs/2.2/mod/mod_ssl.html#sslcarevocationfile">the mod_ssl documentation</a>. |
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| 224 | </p> |
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| 225 | </td></tr><tr><td valign="center" align="left"><code>SSLCARevocationPath</code></td><td valign="center" align="left"> |
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| 226 | <p> |
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| 227 | See <a href="http://httpd.apache.org/docs/2.2/mod/mod_ssl.html#sslcarevocationpath">the mod_ssl documentation</a>. |
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| 228 | </p> |
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| 229 | </td></tr></table> |
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| 230 | |
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| 231 | <p> |
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| 232 | An example SSL Connector declaration can be: |
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| 233 | <div align="left"><table border="0" cellpadding="0" cellspacing="4"><tr><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr><tr><td width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#ffffff"><pre> |
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| 234 | <Connector port="443" maxHttpHeaderSize="8192" |
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| 235 | maxThreads="150" minSpareThreads="25" maxSpareThreads="75" |
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| 236 | enableLookups="false" disableUploadTimeout="true" |
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| 237 | acceptCount="100" scheme="https" secure="true" |
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| 238 | SSLEnabled="true" |
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| 239 | SSLCertificateFile="${catalina.base}/conf/localhost.crt" |
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| 240 | SSLCertificateKeyFile="${catalina.base}/conf/localhost.key" /></pre></td><td width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr><tr><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td><td height="1" width="1" bgcolor="#023264"><img border="0" hspace="0" vspace="0" height="1" width="1" src="./../images/void.gif"></td></tr></table></div> |
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| 241 | </p> |
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| 242 | |
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| 243 | </blockquote></td></tr></table> |
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| 244 | |
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| 245 | <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="AJP"><strong>AJP</strong></a></font></td></tr><tr><td><blockquote> |
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| 246 | |
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| 247 | <p> |
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| 248 | When APR is enabled, the AJP connector will use a socket poller for keepalive, increasing |
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| 249 | scalability of the server. As AJP is designed around a pool of persistent (or almost |
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| 250 | persistent) connections, this will reduce significantly the amount of processing threads |
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| 251 | needed by Tomcat. Unlike the HTTP connector, the AJP connector cannot use sendfile to optimize |
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| 252 | static file processing. |
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| 253 | </p> |
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| 254 | |
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| 255 | <p> |
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| 256 | The following attributes are supported in the AJP APR connector in addition to the ones supported |
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| 257 | in the regular AJP connector: |
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| 258 | </p> |
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| 259 | |
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| 260 | <table cellpadding="5" border="1"><tr><th bgcolor="#023264" width="15%"><font color="#ffffff">Attribute</font></th><th bgcolor="#023264" width="85%"><font color="#ffffff">Description</font></th></tr><tr><td valign="center" align="left"><code>pollTime</code></td><td valign="center" align="left"> |
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| 261 | <p>Duration of a poll call. Lowering this value will slightly decrease latency of connections |
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| 262 | being kept alive in some cases, but will use more CPU as more poll calls are being made. The |
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| 263 | default value is 2000 (5ms).</p> |
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| 264 | </td></tr><tr><td valign="center" align="left"><code>pollerSize</code></td><td valign="center" align="left"> |
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| 265 | <p>Amount of sockets that the poller responsible for polling kept alive connections can hold at a |
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| 266 | given time. Extra connections will be closed right away. The default value is 8192, corresponding to |
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| 267 | 8192 keepalive connections.</p> |
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| 268 | </td></tr></table> |
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| 269 | |
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| 270 | </blockquote></td></tr></table> |
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| 271 | |
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| 272 | </blockquote></td></tr></table></td></tr><!--FOOTER SEPARATOR--><tr><td colspan="2"><hr size="1" noshade></td></tr><!--PAGE FOOTER--><tr><td colspan="2"><div align="center"><font size="-1" color="#525D76"><em> |
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| 273 | Copyright © 1999-2008, Apache Software Foundation |
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| 274 | </em></font></div></td></tr></table></body></html> |
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