httpd tomcat

install apache on VM1

yum install -y httpd

start apache

sudo systemctl start httpd

starts at boot

sudo systemctl enable httpd

install apxs

yum install httpd-devel

  • find / -name apxs
  • which apxs (this file path will be used in ./configure below)

install gcc

yum install -y gcc*
yum install autoconf
yum install libtool

install mod_jk

wget http://www.eu.apache.org/dist/tomcat/tomcat-connectors/jk/tomcat-connectors-1.2.46-src.tar.gz
tar -xf tomcat-connectors-1.2.46-src.tar.gz
cd tomcat-connectors-1.2.46-src/native
./buildconf.sh
./configure –with-apxs=/usr/bin/apxs
make && make install
(find / -name mod_jk.so
/usr/lib64/httpd/modules/mod_jk.so)

Configure httpd.conf

Now that you’ve installed mod_jk, you need to configure it in your httpd.conf file so that you can use it.
You can find httpd.conf in the ‘conf’ directory of your Apache HTTPD home folder.
If httpd in installed by ‘yum install httpd’, this file is
/etc/httpd/conf/httpd.conf

mod_jk requires two entities:

  • mod_jk.xxx - The Apache HTTP Server module, depending on your operating system, it will be mod_jk.so, mod_jk.nlm or MOD_JK.SRVPGM (see the build section).
  • workers.properties - A file that describes the host(s) and port(s) used by the workers (Tomcat processes). A sample workers.properties can be found under the conf directory in the source download.

The configuration provided below, based on the Tomcat documentation, is the minimum configuration required for mod_jk to run correctly.

#Load mod_jk module
LoadModule jk_module /usr/lib64/httpd/modules/mod_jk.so
# Add the module (activate this lne for Apache 1.3)
# AddModule mod_jk.c
# Where to find workers.properties
JkWorkersFile /etc/httpd/conf/workers.properties
# Where to put jk shared memory
JkShmFile /var/log/httpd/mod_jk.shm
# Where to put jk logs
JkLogFile /var/log/httpd/mod_jk.log
# Set the jk log level [debug/error/info]
JkLogLevel info
# Send requests for context /examples to worker named worker1
# 至于为什么 balancer，https://tomcat.apache.org/connectors-doc/common_howto/loadbalancers.html
JkMount /playbook/* balancer

set up two tomcat on VM2, VM3

wget http://ftp.mirror.tw/pub/apache/tomcat/tomcat-8/v8.5.38/bin/apache-tomcat-8.5.38.tar.gz

Configure workers.properties

The workers.properties file defines a list of Tomcat ‘workers’ to which Apache HTTPD can pass requests.
8009 is the ajp port

1
2
3
4
5
worker.node1.host=192.168.77.131
worker.node1.port=8009

worker.node2.host=192.168.77.132
worker.node2.port=8009

test

start two tomcat
可以在两台tomcat里面都放一个playbook
第一台里面放一个webapp/playbook/1.txt, 内容是I am node1
第一台里面放一个webapp/playbook/1.txt, 内容是I am node2
systemctl restart httpd
现在访问
http://192.168.77.130/playbook/1.txt
会发现I am node1和I am node2交替出现
如果强制停止一台tomcat，整个服务不会中断

refer

systemctl start httpd
systemctl restart/start/status httpd
https://tomcat.apache.org/connectors-doc/webserver_howto/apache.html
https://www.mulesoft.com/tcat/apache-tomcat-mod-jk-connector-configuration
https://tomcat.apache.org/connectors-doc/common_howto/workers.html
https://tomcat.apache.org/connectors-doc/common_howto/loadbalancers.html