Apache closes idle AJP/1.3 connections to Tomcat server. However, for some reasons, these connection close connection requests do not result in closing and clearing of corresponding connections at the Tomcat server end. As a result, over a period of time, there will be too many open connections at the Tomcat server end resulting in queuing/rejection of new connection requests from the Apache server. This issue is mostly because of caused by incorrect firewall rules.
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