We currently have a Windows2000 Apache box that forwards all requests to a RedHat EL3 box running JBoss3.2.3(Tomcat). This works great most of the times -- however we do get sporadic 500 errors on the Apache box (like the Tomcat box doesn't fulfill the requests), and a refresh of the page fixes it. This is under a light load. We haven't been able to fix it.
Our one thought is the mismatch in threading models between the Windows/Apache box and the RHEL3/Jboss box is causing it. So, we are looking to keep the Windows/Apache box as our public access point, and use mod_proxy to Tomcat forward requests to Apache on the RHEL3, that will then use mod_jk2 to forward it to Tomcat. We are hoping that this combination will be more stable -- mod_proxy seems to be pretty robust, and we are hoping that mod_jk2 on the same machine will be as well. Now the question is, if Tomcat and HTTPD are on the same machine (RHEL3), what is the best protocol channel to use between the two. TCP seems to be the safest, but potentially the slowest. JNI is not really an option since we are using the embedded Tomcat inside of Jboss. That also leaves the channelUnix option. So, any experience in what is the best option? (In both stability and performance?) If it is channelUnix, I just now need to figure out this crazy 'undefined symbols: apr_md5_final' error. Thanks in advance!
