19.6.3. Install the mod_jk Module Into the Apache HTTP Server (ZIP)
- To perform this task, you must be using Apache HTTP Server installed on a supported environment or the Apache HTTP Server installed in JBoss Enterprise Web Server. Note that the Apache HTTP Server installed in JBoss Enterprise Web Server is part of the JBoss EAP 6 distribution.
- If you need to install Apache HTTP Server, use the instructions in the Red Hat Enterprise Linux Deployment Guide.
- If you need to install JBoss Enterprise Web Server, use the instructions from the JBoss Enterprise Web Server Installation Guide.
- If you are using Apache HTTP Server, download the JBoss EAP 6 Native Components package for your platform from the Red Hat Customer Portal at https://access.redhat.com. This package contains both the
mod_clusterbinaries precompiled for Red Hat Enterprise Linux. If you are using JBoss Enterprise Web Server, it already includes the binary for
- If you are using Red Hat Enterprise Linux (RHEL) 5 and native Apache HTTP server (httpd 2.2.3), load the mod_perl module prior to loading mod_jk module.
- You must be logged in with administrative (root) privileges.
Procedure 19.11. Install the mod_jk Module
Configure the mod_jk module.
- Create a new file called
HTTPD_HOME/conf.d/mod-jk.confand add the following to it:
JkMountdirective specifies which URLs Apache should forward to the mod_jk module. Based on the directive's configuration, mod_jk forwards the received URL to the correct Servlet containers.To serve static content directly, and only use the load balancer for Java applications, the URL path should be
/application/*. To use mod_jk as a load balancer, use the value
/*, to forward all URLs to mod_jk.
# Load mod_jk module # Specify the filename of the mod_jk lib LoadModule jk_module modules/mod_jk.so # Where to find workers.properties JkWorkersFile conf/workers.properties # Where to put jk logs JkLogFile logs/mod_jk.log # Set the jk log level [debug/error/info] JkLogLevel info # Select the log format JkLogStampFormat "[%a %b %d %H:%M:%S %Y]" # JkOptions indicates to send SSK KEY SIZE JkOptions +ForwardKeySize -ForwardDirectories # JkRequestLogFormat JkRequestLogFormat "%w %V %T" # Mount your applications # The default setting only sends Java application data to mod_jk. # Use the commented-out line to send all URLs through mod_jk. # JkMount /* loadbalancer JkMount /application/* loadbalancer # Add shared memory. # This directive is present with 1.2.10 and # later versions of mod_jk, and is needed for # for load balancing to work properly JkShmFile logs/jk.shm # Add jkstatus for managing runtime data <Location /jkstatus/> JkMount status Order deny,allow Deny from all Allow from 127.0.0.1 </Location>Look over the values and ensure they are reasonable for your setup. When you are satisfied, save the file.
Specify a JKMountFile directiveIn addition to the JKMount directive in the
mod-jk.conf, you can specify a file which contains multiple URL patterns to be forwarded to mod_jk.
- Add the following to the
# You can use external file for mount points. # It will be checked for updates each 60 seconds. # The format of the file is: /url=worker # /examples/*=loadbalancer JkMountFile conf/uriworkermap.properties
- Create a new file called
HTTPD_HOME/conf/uriworkermap.properties, with a line for each URL pattern to be matched. The following example shows examples of the syntax of the file.
# Simple worker configuration file /*=loadbalancer
Copy the mod_jk.so file to the httpd's modules directory
NoteThis is only necessary if the Apache HTTP server does not have
modules/directory. You can skip this step if you are using the Apache HTTP server included as a download as part of JBoss EAP 6.Extract the Native Web Server Connectors Zip package. Locate the
mod_jk.sofile in either the
EAP_HOME/modules/system/layers/base/native/lib64/httpd/modules/directories, depending on whether your operating system is 32-bit or 64-bit.Copy the file to the
Configure the mod_jk worker nodes.
- Create a new file called
HTTPD_HOME/conf/workers.properties. Use the following example as your starting point, and modify the file to suit your needs.
# Define list of workers that will be used # for mapping requests worker.list=loadbalancer,status # Define Node1 # modify the host as your host IP or DNS name. worker.node1.port=8009 worker.node1.host=node1.mydomain.com worker.node1.type=ajp13 worker.node1.ping_mode=A worker.node1.lbfactor=1 # Define Node2 # modify the host as your host IP or DNS name. worker.node2.port=8009 worker.node2.host=node2.mydomain.com worker.node2.type=ajp13 worker.node2.ping_mode=A worker.node2.lbfactor=1 # Load-balancing behavior worker.loadbalancer.type=lb worker.loadbalancer.balance_workers=node1,node2 worker.loadbalancer.sticky_session=1 # Status worker for managing load balancer worker.status.type=statusFor a detailed description of the syntax of the
workers.propertiesfile, and advanced configuration options, see Section 19.6.5, “Configuration Reference for Apache Mod_jk Workers”.
Restart the Web Server.The way to restart the web server depends on whether you are using Red Hat Enterprise Linux's Apache HTTP server or the Apache HTTP server included in JBoss Enterprise Web Server. Choose one of the following methods.
Red Hat Enterprise Linux's Apache HTTP ServerIssue the following command:
service httpd restart
JBoss Enterprise Web Server Apache HTTP ServerJBoss Enterprise Web Server runs on both Red Hat Enterprise Linux and Microsoft Windows Server. The method for restarting the web server is different for each.
Red Hat Enterprise Linux, installed from RPMIn Red Hat Enterprise Linux, JBoss Enterprise Web Server installs its web server as a service. To restart the web server, issue the following two commands:
[root@host ~]# service httpd stop [root@host ~]# service httpd start
Red Hat Enterprise Linux, installed from ZipIf you have installed the JBoss Enterprise Web Server Apache HTTP server from a Zip archive, use the
apachectlcommand to restart the web server. Replace EWS_HOME with the directory where you unzipped JBoss Enterprise Web Server Apache HTTP server.
[root@host ~]# EWS_HOME/httpd/sbin/apachectl restart
Microsoft Windows ServerIssue the following commands in a command prompt with administrative privileges:
C:\> net stop Apache2.2 C:\> net start Apache2.2
SolarisIssue the following commands in a command prompt with administrative privileges. Replace EWS_HOME with the directory where you unzipped JBoss Enterprise Web Server Apache HTTP server.
[root@host ~] EWS_HOME/httpd/sbin/apachectl restart
The Apache HTTP server is now configured to use the mod_jk load balancer. To configure JBoss EAP 6 to be aware of mod_jk, see Section 19.3.6, “Configure JBoss EAP 6 to Accept Requests From External Web Servers”.