My host's operating system is RedHat Enterprise. After I had installed Tomcat, I found the following logs in cataline.out when starting or stopping Tomcat:
Starting Tomcat:
Stopping Tomcat:
The cause is that APR(Apache Portable Runtime) has not been installed. I took the following steps to resolve the issue.
Prerequisites for installing APR
APR support requires three main native components to be installed:
- APR library
- JNI wrappers for APR used by Tomcat (libtcnative)
- OpenSSL libraries
- ./configure
- make
- make install (root is required)
- cd tomcat-native-1.1.12-src/jni/native
- ./configure --with-apr=/usr/local/apr
- make
- make install(root is required)
Because OpenSSL had already been installed on my host, only the first two components were to be installed.
What is APR
The mission of the Apache Portable Runtime (APR) project is to create and maintain software libraries that provide a predictable and consistent interface to underlying platform-specific implementations. The primary goal is to provide an API to which software developers may code and be assured of predictable if not identical behaviour regardless of the platform on which their software is built, relieving them of the need to code special-case conditions to work around or take advantage of platform-specific deficiencies or features.
In fact, I don't know why APR is needed. I use Tomcat as a container for my applications implemented with Java which is portable among different operating systems. The roles of APR should be studied later.
Download and Install APR core
APR core 1.3.3 was downloaded from Apache's site. The package is apr-1.3.3-tar.gz.
After extracting the package, the following steps were taken(refer to [2]):
As a result APR libraries were installed in /usr/local/apr.
Download and install JNI wrapper
In Tomcat's binary package, there is a source code package bin/tomcat-native.tar.gz. After extracting it, the following steps were taken:
As a result tcnative libraries were installed in /usr/local/apr/lib
Use APR libraries
Tomcat should be told where to find APR libraries. I guess there are a few ways to tell it. I take the following way:
Add a new environment variable to the Linux user who starts Tomcat server.
After all had been done, the following log messages were found when starting Tomcat:
Sep 30, 2008 4:32:55 PM org.apache.coyote.http11.Http11AprProtocol start
INFO: Starting Coyote HTTP/1.1 on http-8080
Sep 30, 2008 4:32:55 PM org.apache.coyote.ajp.AjpAprProtocol start
INFO: Starting Coyote AJP/1.3 on ajp-8009
The following log messages were found when stopping Tomcat:
Sep 30, 2008 4:27:06 PM org.apache.coyote.http11.Http11AprProtocol destroy
INFO: Stopping Coyote HTTP/1.1 on http-8080
Sep 30, 2008 4:27:06 PM org.apache.coyote.ajp.AjpAprProtocol destroy
INFO: Stopping Coyote AJP/1.3 on ajp-8009
APR was installed successfully.
The mission of the Apache
The mission of the Apache Portable Runtime (APR) project is to create and maintain software libraries that provide a predictable and consistent interface to underlying platform-specific implementations. The primary goal is to provide an API to which software developers may code and be assured of predictable if not identical behaviour regardless of the platform on which their software is built, 117-101 relieving them of the need to code special-case conditions to work around or take advantage of platform-specific deficiencies or features.
Thanks for giving proper
Thanks for giving proper direction how to install APR.I was modifying my site about web hosting and i have faced the problem of installing APR files so, i have searched it on net, found your forum and believe me i felt happiness to see the procedure how to install it.I just follow the procedure and get installed.I have paid regards to my friend Bluehost who also guided me to accomplish the problem.
Re: Install APR（Apache Portable Runtime for Tomcat
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