Running DSpace on Apache HTTPD and Tomcat using the mod_jk connector
Note: These instructions are for Linux, and may be somewhat specific to Red Hat Enterprise Linux 3.2.3-52 and the following software versions (but hopefully they are still helpful for other distros)
- DSpace 1.3.x and above
- Apache HTTPD 2.0.46
- Tomcat 5.5.9 and above
Anyone who has successfully set up
mod_jk connector under different conditions should feel free to add their notes!
- Instructions for Gentoo Linux can be found at http://gentoo-wiki.com/index.php?title=HOWTO_Apache2_and_Tomcat5&redirect=no
Step 1 - Check if mod_jk is installed
Check to see if the
mod_jk connector is installed. Most likely (at least on Red Hat), it should be in
/etc/httpd/modules/ . However, you can try to locate it using the following command:
If there is no response, then
mod_jk is not installed. Otherwise, if it is installed, you can obviously skip the next step!
Step 2 - Install mod_jk from source
(1) Login as the root user. (or someone with "root"-like privileges)
(2) Before trying to build
mod_jk, you must make sure you have the following pre-requisite programs installed (use the
which command to check for each):
antshould already be installed (since it's necessary for DSpace). If
autoconfare missing (both should be in
/usr/bin), download the source and compile using the following commands:
(3) In addition, you must have the Apache Web Server development tools installed. A quick way to check for this is to check for the APache eXtenSion tool (
apxs). It should probably be in
/usr/sbin, if installed:
apxs is missing, you can use the following command in Red Hat to install the
httpd-devel RPM as root (Other distros may need to find and install this RPM through other means):
(4) Download the latest
mod_jk source from the Tomcat Download site http://jakarta.apache.org/site/downloads/downloads_tomcat.html.
(5) Unzip the contents into your home directory:
(6) Configure the connectors with the path to the
apxs file on your system:
mod_jk with the following command:
(8) Assuming all went well, the
mod_jk.so file will be created in the
apache-2.0 subdirectory. You need to copy this file to Apache's shared object files directory (e.g.
/etc/httpd/modules/). From the same
jk/native directory run the following:
(9) In addition, copy the sample workers.properties file to the Apache configuration directory (e.g.
/etc/httpd/conf/). Assuming you are still in the
jk/native directory, run the following commands:
Step 3 - Configure workers.properties
mod_jk connector has been installed, you will have to configure Apache to use this connector to communicate with Tomcat. First, modify the existing
workers.properties.minimal file (should be in
/etc/httpd/conf/ , or wherever you copied it to in Step 2 above):
You will need to modify the following Tomcat and Java home directories:
Also add ajp13 to the worker list:
In addition, you may need to uncomment (and possibly change) the JVM for Unix:
For later versions of mod_jk (I installed 1.2.40) worker.iprocess.jvm_lib is deprecated and would throw an warning. I omitted this line with no problems.
Note: initially the path above was
However, the correct path of the
libjvm.so (at least for Red Hat) is
java/jre/lib/i386/server/libjvm.so (i.e. "
server/libjvm.so", not "
Step 4 - Configure mod_jk connector
Next, you need to create a configuration file for the
mod_jk module (alternatively, you could just add the following configuration directly into your Apache
httpd.conf. I just like to separate things out a bit). In the
/etc/httpd/conf.d/ directory (or whatever directory holds your external configuration files, which
httpd.conf loads), create a file called
jk.conf which has the following content (make sure to edit any paths so they are valid on your server!):
The big thing to pay attention to is the context which you specify in
JkMount! If you specify
/dspace/*, then only requests to
http://my-host-name/dspace/* will be forwarded to Tomcat! However, if you specify
/*, then all requests to
http://my-host-name/* will be forwarded to Tomcat.
You can get a little tricky by doing something like:
Notice, first you specify that all requests should be forwarded to Tomcat. But, then for specific UI's you can specify to ignore
mod_jk (using the
no-jk environment variable). So, the above specifies that everything except paths matching
http://my-host-name/anotherApp/* are forwarded to Tomcat.
Step 5 - Configure Tomcat
Next, you need to take a look at the Tomcat
server.xml configuration file (in the
/conf} subdirectory, whereever Tomcat is installed). Ensure that the following AJP 1.3 Connector is uncommented:
Make sure that the
port specified corresponds to the port you defined for the
ajp13 worker (this port number is defined in the
workers.properties file, as shown above). In addition, make sure the
UIEncoding is set to
tomcatAuthentication is set to
false (assuming you want authentication taken care of in Apache rather than Tomcat). Finally, make sure you set the
redirectPort to be the port that Tomcat is running on (usually either 8443, for HTTPS, or 8080, for HTTP).
Step 6 - Restart everything and Test!
Restart Tomcat and Apache!
Now, test the connection between Apache and Tomcat. You should now be able to get to DSpace whether you specify port 8080 (for Tomcat) or not. For example, the following URLs should bring you to the same DSpace (you may need to replace localhost with your server path):
Hopefully everything works for you! If it doesn't, ask questions to the Mailing Lists. If you find any problems with the above instructions, feel free to edit and enhance them!