chrisipa/tomcat repository overview

⁠Apache Tomcat

Apache Tomcat docker image based on Debian Jessie and Oracle JDK 8.

⁠Source Code

Sources to build this docker image can be found here⁠.

⁠Description

This Tomcat docker image contains the following software components:

• Oracle JDK 8⁠
• Apache Tomcat 9⁠

⁠Ports

These tcp ports are exposed:

• 8080 (http)
• 8443 (https)

⁠How to run the container

⁠Environment variables

When you start the Tomcat container, you can adjust the configuration by passing one or more environment variables on the docker run command line:

⁠CATALINA_OPTS

• Java runtime options used when the "start", "run" or "debug" command is executed
• Default value: -

⁠TOMCAT_SESSION_TIMEOUT

• Tomcat session timeout in minutes
• Default value: 30

⁠Using docker

⁠Preparation: Create a underprivileged user on the host system

1. Create group and user:

sudo groupadd -g 1001 chrisipa
sudo useradd -u 1001 -g 1001 -m -s /usr/sbin/nologin chrisipa

### Example 1: Run evaluation version

1. Run the Tomcat container with the following command:

docker run --rm -p 8080:8080 -p 8443:8443 chrisipa/tomcat

### Example 2: Run Tomcat container with java memory options for max heap size

1. Run the Tomcat container with the following command:

docker run --rm -p 8080:8080 -p 8443:8443 -e "CATALINA_OPTS=-Xmx768m" chrisipa/tomcat

### Example 3: Run your own web application in daemon mode

1. Create webapps folder on host system:

sudo mkdir -p /opt/tomcat/webapps

2. Copy your own war to webapps folder:

sudo cp my-app.war /opt/tomcat/webapps

3. Change permissions on webapps folder:

sudo chown -R 1001.1001 /opt/tomcat/webapps

4. Run the Tomcat container with the following command:

docker run -d -p 8080:8080 -p 8443:8443 -v /opt/tomcat/webapps:/opt/tomcat/webapps chrisipa/tomcat

## Advanced topics

### Use your own SSL certificates

1. Generate your own Java keystore file named `keystore` with password `changeit` by answering all questions:

keytool -genkey -alias tomcat -keyalg RSA -keysize 2048 -keystore keystore

2. Generate a CSR from your newly generated Java keystore:

keytool -certreq -alias tomcat -file csr.txt -keystore keystore

3. Upload your `csr.txt` to your SSL provider and generate a P7B SSL certificate for tomcat

4. Import the generated P7B SSL certificate into your Java keystore:

keytool -import -trustcacerts -alias tomcat -file your_site_name.p7b -keystore keystore

5. Place your Java keystore in a folder of your choice and mount it to the `/opt/ssl/tomcat` folder of your docker container:

-v /opt/ssl/tomcat:/opt/ssl/tomcat