Re: Apache/Tomcat/mod_jk/Linux - Error 500 when trying to send a hessian request via load balancer to tomcat application

[Frederik Nosi <frederik.nosi@xxxxxxxxxxx>]

Hi,

On 06/19/2014 06:05 PM, Dave McGee wrote:

Hi all,

First post here so please be gentle, haha! I am working with an Apache / Tomcat cluster / mod_jk / Linux setup:

- An Apache HTTP Server acting as a Load Balancer

- 2 Tomcat Servers (Node A and Node B)

- We have a Java/Grails application being hosted on each of the Tomcat servers.

- We're migrating in behind a customer firewall and we're seeing issues with the following application error when we try make our hessian request:

I had a very similar problem to this, are you using "use_server_errors" on your uriworkermap.properties? If so that's it, when using hessian you have to disable it.

 com.caucho.hessian.client.HessianConnectionException: 500: java.io.IOException: Server returned HTTP response code: 500 for URL.

- We've been able to verify all firewalls and security packages are turned off. We've also been able to verify there is an error in the load balancer access log everytime this hessian call fails (/var/log/httpd/access_log) :

10.30.95.51 - - [19/Jun/2014:11:55:13 -0400] "POST /Ticketer/hessian/RemoteTicketService HTTP/1.1" 500 8067 "-" "Java/1.6.0_30"

Does anyone have any tips on how I could troubleshoot this further, or has anyone experienced something like this in the past?

Another tip, do a tcpdump between apache and tomcat (with -s0), this way you can see what's passing on the wire.

Regards,
Dave