Mod_jk NEED HELP!!!

[Javier Hernandez]

Has anyone been sucessuful in compiling mod_jk for apache 2 on RedHat 7.2 I am not able to compile it when I run Ant here is the error I get. PLEASE HELP =(
Buildfile: build.xml
init:
[echo] /root
[taskdef] Could not load definitions from resource META-INF/ant.tasks. It could not be found.
[mkdir] Created dir: /root/jakarta-tomcat-connectors-4.1.10-src/jk/build/jk
apache20:
[mkdir] Created dir: /root/jakarta-tomcat-connectors-4.1.10-src/jk/build/jk/apache2
BUILD FAILED
file:/root/jakarta-tomcat-connectors-4.1.10-src/jk/native/build.xml:134: Could not create task or type of type: so.
Ant could not find the task or a class this task relies upon.
This is common and has a number of causes; the usual
solutions are to read the manual pages then download and
install needed JAR files, or fix the build file:
- You have misspelt 'so'.
Fix: check your spelling.
- The task needs an external JAR file to execute
and this is not found at the right place in the classpath.
Fix: check the documentation for dependencies.
Fix: declare the task.
- The task is an Ant optional task and optional.jar is absent
Fix: look for optional.jar in ANT_HOME/lib, download if needed
- The task was not built into optional.jar as dependent
libraries were not found at build time.
Fix: look in the JAR to verify, then rebuild with the needed
libraries, or download a release version from apache.org
- The build file was written for a later version of Ant
Fix: upgrade to at least the latest release version of Ant
- The task is not an Ant core or optional task
and needs to be declared using <taskdef>.
Remember that for JAR files to be visible to Ant tasks implemented
in ANT_HOME/lib, the files must be in the same directory or on the
classpath
Please neither file bug reports on this problem, nor email the
Ant mailing lists, until all of these causes have been explored,
as this is not an Ant bug.

[Jason Kretzer]

First off, I would not use the mod_jk on Linux. I have found it to be buggy at best. I would use mod_webapp.so it has never failed me.
I would also suggest going to this website:
Galatea
They have some of the best guides.
I hope this helps.

[Javier Hernandez]

Yeah I found that site to be very helpful! Thanks a lot!

[Javier Hernandez]

But doesn't mod_webapp have some serious limitations? I need to run this combo in an production enviornment.

[Richard Blaylock]

Of the people using Tomcat as an app server and Apache httpd as a web server in front of it, I would be interested to know who is using mod_jk and who is using mod_webapp.
Apparently there is now a JK2 connector (also known as Coyote) which replaces JK, so I'd also be interested to know if people have had success with that, and especially if people know advantages/disadvantages of one connector over another.
Thanks,
Richard

[Jesse Beaumont]

Hi,
I'm not exactly sure what coyote offers over JK and webapp, but some of the differences between mod_jk and webapp are that mod_jk supports load balancing which is obviously essential when running a cluster of tomcat servers (this includes "sticky" sessions (aka session affinity), transparent failover, transparent failback) which mod_webapp to my knowledge doesn't. Mod_webapp has the advantage that it supports the deploying and undeploying of webapps dynamically which mod_jk doesn't.
I would suspect that coyote supports load balancing as well, and given that tomcat 4.1 now supports a JMX engine, I guess the dynamic deploy of webapps via the connector is no longer such an issue, but I don't have any practical experience with this.
Jesse

[Timothy Stone]

Jesse has touched on all the important issues... but some follow up and a wonderful link as well...
JK2 is experimental at best. It puts JK2 in a Catch 22 of sorts really. There are so many JK deployments in production the barrier to entry for JK2 is high. JK2 in production environments where security is an issue is probably a "no-no" because of the lack of user adoption and security hammering. I would stick with JK in any established production environment. That's just my opinion.
Finally, Jesse points out all the pluses of JK... which I would like to supplement with a great HOW-TO, for Linux environments no less (mod_webapp as noted has no support for all the cool features we want in a web application so I don't know why it's called mod_webapp in the first place; as to the stability issue of JK in Linux, I need more proof... it has been rock solid in my production environment, both on Linux and Win2k running Apache 1.3 and 2.0.)
www.ubeans.com
There is a rock solid tute here on setting up a multi-Tomcat environment with Apache. Somewhat dated in versioning, but still applicable. I used this tute in no less than three platforms running Apache 1.3 and 2.0.4x on Windows, Linux and Mac OS X. Kudos to the author. The tute is the basis for a current production environment running Lucene as a search engine.
So to answer Richard's query... mod_jk, Apache 2.0.43 in Windows. Solid. I should also state that we are about to deploy another application with JK2 and Tomcat 4.1.1x (minus Apache however). I cannot comment further as it is still playing in a sandbox while all the crap surrounding Win2k services is worked out. Win2k just doesn't have a good model for "daemons."
[ October 29, 2002: Message edited by: Timothy Stone ]