How to install Tomcat 8.5 on Debian 8

Introduction

Apache Tomcat is a Java Servlet Container which implements several Java EE specifications including JavaServer Pages (JSP), Java Servlet, WebSocket and Java EL. It  also provides an HTTP web server environment in which Java code can run. It’s distributed under the Apache License 2.0.

This tutorial explains how to install and configure Tomcat 8.5.11 on Debian 8.

Getting started

Install Java

The first thing to do is to install python-software-properties, for managing repository:

# apt install python-software-properties -y

Next, add required repository:

# echo "deb http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main" | tee /etc/apt/sources.list.d/webupd8team-java.list
# echo "deb-src http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main" | tee -a /etc/apt/sources.list.d/webupd8team-java.list
# apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys EEA14886
# apt update

Now, you can install Java:

# apt install oracle-java8-installer -y

Accept the licence, and then wait for the installation process to complete. Next, check Java version:

# java -version

just to be sure that everything went well.

Configure JAVA_HOME

Now you need to configure the environment variable (JAVA_HOME) on the server:

# update-alternatives --config java

You should see the following Java path: /usr/lib/jvm/java-8-oracle/jre/bin/java
Edit the environment file /etc/environment, adding the following line:

JAVA_HOME="/usr/lib/jvm/java-8-oracle/jre"

Save and exit.

Next, edit ~/.bashrc writing the lines:

JAVA_HOME=/usr/lib/jvm/java-8-oracle/jre
export JAVA_HOME
PATH=$JAVA_HOME/bin:$PATH
export PATH

Save, exit and reload the file:

# source ~/.bashrc

Now, executing the command:

# echo $JAVA_HOME

you should read the correct path to Java.

Install Tomcat

Once you have configured Java, it’s time to install Apache Tomcat. For that, we will use a “tomcat” as the user and group:

# groupadd tomcat
# useradd -s /bin/false -g tomcat -d /opt/tomcat tomcat

With this command we created a user named tomcat, which uses /opt/tomcat as the home directory. In /opt, download Tomcat:

# cd /opt && wget http://apache.panu.it/tomcat/tomcat-8/v8.5.11/bin/apache-tomcat-8.5.11.tar.gz

Next, extract the Tomcat archive.

# tar xzvf apache-tomcat-8.5.11.tar.gz

Rename the extracted folder “tomcat”:

# mv apache-tomcat-8.5.11 tomcat

Then, change the owner to the ‘tomcat’ user, and make all the files in the bin directory executable. To accomplish this, execute the following commands:

# chown -hR tomcat:tomcat tomcat
# chmod +x tomcat/bin/*

Next, you’ll need to define $CATALINA_HOME, which is an environment variable pointing to the base path of the Tomcat installation. In the ~/.bashrc write:
export CATALINA_HOME=/opt/tomcat
and reload the file:

# source ~/.bashrc

Testing Apache Tomcat

In $CATALINA_HOME/bin there is a script, startup.sh. This starts and checks Tomcat. So, executing:

# $CATALINA_HOME/bin/startup.sh

you should see the following output:

Using CATALINA_BASE:   /opt/tomcat
Using CATALINA_HOME:   /opt/tomcat
Using CATALINA_TMPDIR: /opt/tomcat/temp
Using JRE_HOME:        /usr/lib/jvm/java-8-oracle/jre
Using CLASSPATH:       /opt/tomcat/bin/bootstrap.jar:/opt/tomcat/bin/tomcat-juli.jar
Tomcat started.

Make sure that the last line is “Tomcat started.”; this means that Tomcat is correctly installed.

Tomcat uses the port 8080, so check that everything is okay:

# netstat -plntu | grep 8080

Result should be like this one:
tcp6 0 0 :::8080 :::* LISTEN 3294/java

With your browser, go to the URL: localhost:8080

You should see the following page:

If you see this page it means that Tomcat is up and running correctly.
To shut down Tomcat, use this script:

# $CATALINA_HOME/bin/shutdown.sh

Create a systemd service

Once you have shut down Tomcat, in the systemd system directory, create a new file:

# $EDITOR /etc/systemd/system/tomcat.service

Paste the following configuration:

[Unit]
Description=Apache Tomcat 8 Servlet Container
After=syslog.target network.target

[Service]
User=tomcat
Group=tomcat
Type=forking
Environment=CATALINA_PID=/opt/tomcat/tomcat.pid
Environment=CATALINA_HOME=/opt/tomcat
Environment=CATALINA_BASE=/opt/tomcat
ExecStart=/opt/tomcat/bin/startup.sh
ExecStop=/opt/tomcat/bin/shutdown.sh
Restart=on-failure

[Install]
WantedBy=multi-user.target

Save and exit.
Now, use systemd to start the Tomcat service and then add its service to start at boot time. The commands are:

# systemctl daemon-reload
# systemctl start tomcat
# systemctl enable tomcat

Now Tomcat is running on port 8080.

Configure users

This next step is necessary because we can’t access the site-manager dashboard. So:

# $EDITOR /opt/tomcat/conf/tomcat-users.xml

Under line 43, paste the following content:

<role rolename="manager-gui"/>
<user username="admin" password="password" roles="manager-gui,admin-gui"/>

Next, edit the context.xml file.

# $EDITOR /opt/tomcat/webapps/manager/META-INF/context.xml

Here, comment the following lines:

 <Context antiResourceLocking="false" privileged="true" >
<!--  <Valve className="org.apache.catalina.valves.RemoteAddrValve"
         allow="127\.\d+\.\d+\.\d+|::1|0:0:0:0:0:0:0:1" /> -->
</Context>

Save, exit and restart Tomcat:

# systemctl restart tomcat

Conclusion

That’s all! Now, you can go to localhost:8080/manager/html, which is the manager dashboard.
From now on, you can do everything through your browser. Tomcat 8.5 is running on your Debian 8 server!