When Tomcat stops responding to Apache

Today our multi-node tomcat servers became unresponsive to user/web traffic.  A quick look at our monitoring tools indicated that the tomcat servers were running healthily.  While the application administrator looked at catalina.out to see if we were missing something, I dug into the load balancer logs.  I immediately saw the following errors: [Date] [error] ajp_read_header: […]