Apache Tomcat 7 Essentials

Transcription

1 Apache Tomcat 7 Essentials Learn Apache Tomcat 7 step-by-step through a practical approach, achieving a wide vision of enterprise middleware along with building your servers, and administrating 24x7x365 own middleware Tanuj Khare PUBLISHING open source community experience distilled - BIRMINGHAM MUMBAI

2 Preface 1 Chapter 1: Installation of Tomcat 7 7 History of Tomcat 8 Tomcat support matrix 8 Features and enhancements of Apache Tomcat 7 10 Web application memory leak detection and prevention 10 Servlet Improved logging 11 Aliases 11 Installation of Tomcat 7 12 How to download the Tomcat software 12 Binary package 13 RPM/exe 14 Source 14 Prerequisites for the Tomcat 7 installation 14 Installation of Java 15 Configuration of OS environment variables 21 Installation of Apache Tomcat 7 27 Installation on a Windows environment 27 Installation on a Linux environment 31 Startup and shutdown of Tomcat services 32 Services in Windows 32 Services in Linux 33 Startup script 35 Shutdown script 35 Verification of Tomcat status 36 Common problems and troubleshooting in installation 37 Error: Permission denied for the Java binary 37 Error: Tomcat is not able to find JAVA_HOME 38 Error: Error in the logs showing port already in use 38 Summary 38

3 Table of Contents Chapter 2: Configuration and Deployment 39 Configuration files and their usage 39 Configuration of Tomcat 7 41 DataSource configuration 42 JDBC 44 JNDI 44 DataSource 44 Comparison of the datasource for common databases 49 Tomcat Manager configuration 50 Enabling the Tomcat Manager 51 Context path 55 Enabling the context path 56 Deployment in Tomcat 7 59 Structure of the WebArchive 59 Archive Files 60 Types of deployment 62 Ways of application deployment in Tomcat 7 63 Common issues in deployment, configuration, and their troubleshooting 65 Summary 67 Chapter 3: Performance Tuning 69 Performance tuning for Tomcat 7 69 Why we need performance tuning? 70 How to start performance tuning 71 Tomcat components tuning 73 Types of connectors for Tomcat 7 73 Java HTTP Connector 74 Java AJP Connector 74 APR (AJP/HTTP) Connector 74 Thread optimization for Tomcat 7 75 Shared thread pool (shared executor) 75 Dedicated thread pool 76 Shared thread pool versus dedicated thread pool 76 maxthreads 76 maxkeepalive 77 JVM tuning 77 Why do we need to tune the JDK for Tomcat? 78 JMAP (Memory Map) 79 How to increase the heap size in Tomcat 7 81 Garbage collection 82 JVM options 84 Standard options 84 Non-standard options 85 Parameters displayed in the logs for GC 87

4 SurvivorRatio 87 OS tuning 88 Summary 89 Chapter 4: Integration of Tomcat with the Apache Web Server 91 User request flow (web/application level) 91 Why the Apache HTTP server 92 Installation of the Apache HTTP 93 Apache HTTP installation on Windows 94 How to monitor the Apache service 99 Installation of Apache HTTP on Linux (non-dos environment) 100 Apache Portable Runtime 103 Apache Jserv protocol 109 Installation and configuration of modjk 109 Installation of modjk 110 Configuration of modjk in Apache 112 mod_proxy configuration 116 Comparison between modjk and mod_proxy 117 IIS integration with Tomcat Prerequisites 117 Steps for installation 118 Common issues and troubleshooting for integration 121 Summary 123 Chapter 5: Securing Tomcat Tomcat Manager 125 Tomcat security permissions 126 catalina.properties 126 catalina.policy 127 System Code permissions 127 Catalina Code permissions (Tomcat core permission) 128 Web application permissions 129 tomcat-users.xml 131 server.xml 131 Enabling Tomcat Manager 132 How to enable the Tomcat Manager 132 Securing Tomcat 7 for production 132 Tomcat settings 133 Connector Port 133 Slimming of Tomcat application 134 Disable hot deployment 135 Non-Tomcat settings 135 Service as a separate user 135 Firewall 136 Password 137

5 SSL configuration on Tomcat Types of SSL certificates 139 Process of installing SSL 139 Summary 143 Chapter 6: Logging in Tomcat JULI 145 Loggers, appenders, and layouts 147 Types of logging in Tomcat Application log 149 Server log 149 Console log 149 Access log 151 Host manager 152 Types of log levels in Tomcat Log4j 155 Log level for log4j 155 How to use log4j 156 Log level mapping 157 Values for Tomcat Log analysis 159 Helpful commands for log analysis 160 Summary 161 Chapter 7: Troubleshooting in Tomcat 163 Common problem areas for web administrators 164 How to troubleshoot a problem 165 Slowness issue in applications 165 How to solve slowness issues in Tomcat Troubleshooting at the database level 171 How to obtain a thread dump in Tomcat Thread dump using Kill command 174 Thread dump using jstack 175 How to analyze the thread dump for Tomcat instance 176 Thread dump analysis using Samurai 177 Thread dump analysis using the Thread Dump Analyzer 178 Errors and their solutions 182 JVM (memory) issues 183 Database-related issues 185 Web server benchmarking 188 ApacheBench 188 JMeter 189 Summary 189

6 Chapter 8: Monitoring and Management of Tomcat Different ways of monitoring 192 Monitoring setup for a web application and database server 193 Tomcat Manager in Tomcat Monitoring in Tomcat Summary of the Server Status of Tomcat Complete Server Status of Tomcat JConsole configuration on Tomcat Remote JMX enabling 202 How to connect to the JConsole 203 Different tabs for the JConsole and their features 205 Memory overview 205 Threads overview 206 VM Summary and Overview 207 MBeans 209 Summary 213 Chapter 9: Clustering in Tomcat What is a cluster? 216 Benefits of clustering 216 Disadvantages of clustering 217 Clustering architecture 217 Vertical clustering 218 Advantages of vertical clustering 218 Disadvantages of vertical clustering 219 Horizontal clustering 219 Advantages of horizontal clustering 220 Disadvantages of horizontal clustering 220 Vertical clustering in Apache Tomcat Installation of the Tomcat instance 221 Configuration of a vertical cluster 221 Configuration of instance Configuration of instance Apache web server configuration for vertical clustering 228 Horizontal clustering in Apache Tomcat Installation of the Tomcat instance 230 Configuration of the cluster 230 Configuration of instance Configuration of instance Apache web server configuration for horizontal clustering 235 Testing of the clustered instance 237 Monitoring of Tomcat clustering 238 Summary 239

7 Jjjfrfc of Contents Chapter 10: Tomcat Upgrade 241 Different types of environment 241 Development environment 242 Quality Assurance environment 242 Staging environment 242 Production environment 242 Life cycle of the upgrade 242 Tomcat upgrade from 6 to Prerequisites for Tomcat I nstallation of Tomcat 7 for the upgrade 245 Configuration of Tomcat JVM configuration 247 Database connection settings 248 Application migration 249 Alias configuration 250 ITIL process implementation 250 Availability management 250 Capacity management 251 Service Transition 251 Summary 252 Chapter 11: Advanced Configuration for Apache Tomcat Virtual hosting 254 Name-based virtual hosting 254 IP-based virtual hosting 255 Virtual hosting in Tomcat Hostname aliases 258 Multiple applications hosting on a single Tomcat 7 instance 258 Multiple Tomcat environments Development/QA/Stage/Production 259 Tuning cache 260 Optimization of Tomcat Running Tomcat 7 as a non privileged user 261 Summary 262 Index 263