Solved

Apache HTTP Server/Tomcat Load Balancing Problem

Posted on 2007-03-30
5
793 Views
Last Modified: 2012-08-13
I am trying to load balance our web based application using Apache HTTP Server and Tomcat on Linux.

I think I have setup the environments correctly, although I am not sure of the configuration parameters for either apache or tomcat. We have apache running on one linux server and 2 instances of tomcat running on two nodes with linux installed.

I am using JMeter to test the load on our app. I can get JMeter to send 30 simultanous requests (num of users)  for 4 consecutive intervals in each thread group, however as I change the number of users to 35, I start getting
"HTTP response code: 500
HTTP response message: Internal Server Error" errors.

As I monitor apache's log file, I can see it is receiving all the POST requests, however it seems to me like it is not able to send them all to its workers, tomcat1 and tomcat2, or workers are not capable of accepting and serving these requests.

If you have any suggestions/recommendations on how to configure apache or tomcat to handle more simultanous users, please advise.

I am using:
apache 2.2
mod_jk: download   mod_jk-1.2.21-apache-2.2.x-linux-i686.so
tomcat 5.5.12
jrockit r27

Thank you,
Noushin
0
Comment
Question by:NoushinB
  • 2
5 Comments
 
LVL 30

Expert Comment

by:Mayank S
ID: 18827812
Are there any error logs in Tomcat's logs? 500 internal error would mean some exception was thrown on the server side. Are you closing your connections, etc properly in finally blocks? Also ensure you don't store any state in the servlets and if you do then they should be thread safe. Difficult to say what it is without knowing what your application does.
0
 

Author Comment

by:NoushinB
ID: 18838046
After turning on exception handling, we noticed our calls to web services were timing out. We increased our WS timeout setting and the application proceeded successfully. Thanx.
0
 
LVL 30

Accepted Solution

by:
Mayank S earned 500 total points
ID: 19046537
Yes that is why Tomcat was getting those time out exceptions and showing you a 500 ;)
0
 
LVL 1

Expert Comment

by:Computer101
ID: 20634039
Forced accept.

Computer101
EE Admin
0

Featured Post

Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Over the last year I have answered a couple of basic URL rewriting questions several times so I thought I might as well have a stab at: explaining the basics, providing a few useful links and consolidating some of the most common queries into a sing…
Meet the world's only “Transparent Cloud™” from Superb Internet Corporation. Now, you can experience firsthand a cloud platform that consistently outperforms Amazon Web Services (AWS), IBM’s Softlayer, and Microsoft’s Azure when it comes to CPU and …
Two types of users will appreciate AOMEI Backupper Pro: 1 - Those with PCIe drives (and haven't found cloning software that works on them). 2 - Those who want a fast clone of their boot drive (no re-boots needed) and it can clone your drive wh…
In a recent question (https://www.experts-exchange.com/questions/29004105/Run-AutoHotkey-script-directly-from-Notepad.html) here at Experts Exchange, a member asked how to run an AutoHotkey script (.AHK) directly from Notepad++ (aka NPP). This video…

830 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question