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Running a seperate server process only to proxy all requests to the servlet container is not ideal. At the very least donig doing that means that 2 two servers/services must be correctly configured, integrated and running in order for 1 one web server/service to function (i.e., doubling the potential for service disruptions). None of the approaches introduced above suffer from these issues. Additionally, additionally proxying may introduce performance or timeout problems, problems with proper virtualization of requests, getting the correct IP addresses logged for clients, security issues with HTTP Request Headers set by an external web server / load balancer merely proxying HTTP to the container (which may be forged), etc.
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