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Everything About Apache Tomcat Server

Apache HTTP Server and Tomcat Server (Servlet container with JSP Environment) both reconcile to form Apache Tomcat Server.Apache HTTP Server Serves only Static content e.g. HTML,Images.But Tomcat Server Servers Static as well as Dynamic content e.g. Servlet in Java
So you may ask why are we using Apache Tomcat Server and why not Tomcat only?Actually you can but there are some side where Tomcat is lagging,these are
  •       Tomcat is not as fast as Apache when it comes to static Pages
  •       Tomcat is not as configurable as Apache
  •       Tomcat is not as robust as Apache
Hence in real world ,people uses Apache for static content and Tomcat as Servlet/JSP Add-On.That is Apache Tomcat Server.
There are some question about working of Apache tomcat Server and its one WORD answer,
  1. How will Apache know which request should be forwarded to Tomcat?                            Ans:  httpd.conf
  2. How will apache forward request to Tomcat?                                                                     Ans:   Web server Adaptor library(mod_jk)
  3. How will tomcat Accept and Handle these request?                                                          Ans: server.xml
  4. How will Hosted Application Runs On Server?                                                                  Ans: web.xml
Tomcat Worker is a Tomcat Instance that is waiting to execute servlet on behalf of web server e.g. Apache server.Single server has multiple Applications (Context) Hosted, each Context has Tomcat Worker assigned.

I misses the point that mostly people may jumble you by saying Catallina.What is Catallina?.When you start tomcat Server, you are actually starting Catalina.Catalina is the nothing but the server environment consists of connector and container.It is module of two Connector and Container.
Connector that accept request and sends response’s like a door keeper.Container actually process that Request and response.To change Catalina Behavior that Server default settings, we have six configuration files

1. catalina.policy                -  Tomcat security policy for Catalina Java Class
2.         -  properties for Catalina class and cache setting for performance tuning
3. logging. Properties        -  logger settings
4. content.xml                    - tomcat context information that will loaded for every application running in given instance of tomcat
5. servlet.xml                     - main and global configuration file,containf configuration of various componets
6. tomcat-users.xml          - authentication for tomcat
7. Web.xml                         - configuration for all application that are loaded in tomcat

Catalina.Out is standard destination log file for System.Out and System.err that print information and errors in JVM.


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