nginx+tomcat集群实例

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See the License for the specific language governing permissions and limitations under the License. ================================================================================ =================================================== Running The Apache Tomcat 6.0 Servlet/JSP Container =================================================== Apache Tomcat 6.0 requires a Java Standard Edition Runtime Environment (JRE) version 5.0 or later. ============================= Running With JRE 5.0 Or Later ============================= (1) Download and Install a Java SE Runtime Environment (JRE) (1.1) Download a Java SE Runtime Environment (JRE), release version 5.0 or later, from http://www.oracle.com/technetwork/java/javase/downloads/index.html (1.2) Install the JRE according to the instructions included with the release. You may also use a full Java Development Kit (JDK) rather than just a JRE. (2) Download and Install Apache Tomcat (2.1) Download a binary distribution of Tomcat from: http://tomcat.apache.org/ (2.2) Unpack the binary distribution so that it resides in its own directory (conventionally named "apache-tomcat-[version]"). For the purposes of the remainder of this document, the name "CATALINA_HOME" is used to refer to the full pathname of that directory. NOTE: As an alternative to downloading a binary distribution, you can create your own from the Tomcat source code, as described in "BUILDING.txt". You can either a) Do the full "release" build and find the created distribution in the "output/release" directory and then proceed with unpacking as above, or b) Do a simple build and use the "output/build" directory as "CATALINA_HOME". Be warned that there are some differences between the contents of the "output/build" directory and a full "release" distribution. (3) Configure Environment Variables Tomcat is a Java application and does not use environment variables directly. Environment variables are used by the Tomcat startup scripts. The scripts use the environment variables to prepare the command that starts Tomcat. (3.1) Set CATALINA_HOME (required) and CATALINA_BASE (optional) The CATALINA_HOME environment variable should be set to the location of the root directory of the "binary" distribution of Tomcat. The Tomcat startup scripts have some logic to set this variable automatically if it is absent, based on the location of the startup script in *nix and on the current directory in Windows. That logic might not work in all circumstances, so setting the variable explicitly is recommended. The CATALINA_BASE environment variable specifies location of the root directory of the "active configuration" of Tomcat. It is optional. It defaults to be equal to CATALINA_HOME. Using distinct values for the CATALINA_HOME and CATALINA_BASE variables is recommended to simplify further upgrades and maintenance. It is documented in the "Multiple Tomcat Instances" section below. (3.2) Set JRE_HOME or JAVA_HOME (required) These variables are used to specify location of a Java Runtime Environment or of a Java Development Kit that is used to start Tomcat. The JRE_HOME variable is used to specify location of a JRE. The JAVA_HOME variable is used to specify location of a JDK. Using JAVA_HOME provides access to certain additional startup options that are not allowed when JRE_HOME is used. If both JRE_HOME and JAVA_HOME are specified, JRE_HOME is used. The recommended place to specify these variables is a "setenv" script. See below. (3.3) Other variables (optional) Other environment variables exist, besides the four described above. See the comments at the top of catalina.bat or catalina.sh scripts for the list and a description of each of them. One frequently used variable is CATALINA_OPTS. It allows specification of additional options for the java command that starts Tomcat. See the Java documentation for the options that affect the Java Runtime Environment. See the "System Properties" page in the Tomcat Configuration Reference for the system properties that are specific to Tomcat. A similar variable is JAVA_OPTS. It is used less frequently. It allows specification of options that are used both to start and to stop Tomcat as well as for other commands. Note: Do not use JAVA_OPTS to specify memory limits. You do not need much memory for a small process that is used to stop Tomcat. Those settings belong to CATALINA_OPTS. Another frequently used variable is CATALINA_PID (on *nix only). It specifies the location of the file where process id of the forked Tomcat java process will be written. This setting is optional. It will enable the following features: * better protection against duplicate start attempts and * allows forceful termination of Tomcat process when it does not react to the standard shutdown command. (3.4) Using the "setenv" script (optional, recommended) Apart from CATALINA_HOME and CATALINA_BASE, all environment variables can be specified in the "setenv" script. The script is placed either into CATALINA_BASE/bin or into CATALINA_HOME/bin directory and is named setenv.bat (on Windows) or setenv.sh (on *nix). The file has to be readable. By default the setenv script file is absent. If the script file is present both in CATALINA_BASE and in CATALINA_HOME, the one in CATALINA_BASE is preferred. For example, to configure the JRE_HOME and CATALINA_PID variables you can create the following script file: On Windows, %CATALINA_BASE%\bin\setenv.bat: set "JRE_HOME=%ProgramFiles%\Java\jre6" exit /b 0 On *nix, $CATALINA_BASE/bin/setenv.sh: JRE_HOME=/usr/java/latest CATALINA_PID="$CATALINA_BASE/tomcat.pid" The CATALINA_HOME and CATALINA_BASE variables cannot be configured in the setenv script, because they are used to locate that file. All the environment variables described here and the "setenv" script are used only if you use the standard scripts to launch Tomcat. For example, if you have installed Tomcat as a service on Windows, the service wrapper launches Java directly and does not use the script files. (4) Start Up Tomcat (4.1) Tomcat can be started by executing one of the following commands: On Windows: %CATALINA_HOME%\bin\startup.bat or %CATALINA_HOME%\bin\catalina.bat start On *nix: $CATALINA_HOME/bin/startup.sh or $CATALINA_HOME/bin/catalina.sh start (4.2) After startup, the default web applications included with Tomcat will be available by visiting: http://localhost:8080/ (4.3) Further information about configuring and running Tomcat can be found in the documentation included here, as well as on the Tomcat web site: http://tomcat.apache.org/ (5) Shut Down Tomcat (5.1) Tomcat can be shut down by executing one of the following commands: On Windows: %CATALINA_HOME%\bin\shutdown.bat or %CATALINA_HOME%\bin\catalina.bat st