Docker Image

Runtime Arguments

The following are accepted by the container as runtime arguments.  Options should be followed by a value, flags are stand-alone.  Note that these arguments are passed after the image name in a Docker Run statement.

Options

* - Specify Public address/HTTP/HTTPS ports together, all three must be specified

Flags

Supplemental JVM and Wrapper Arguments

Gateway Arguments

Logging Settings

Unlike the non-containerized version of Ignition, the container image default logging settings have no bounds. Setting size limits will prevent containers with a lot of wrapper logs from causing unnecessary disk space exhaustion. Reference the Docker logging configuration page to specify logger size limits. 

Examples

This section will contain some example run configurations for the Ignition Docker image.  Review these examples to learn a bit more about how to run and configure the Ignition Docker image, as well as some typical best practices.

Deploying an Ephemeral Gateway for Testing

The run statement below will launch a container in detached mode -d, publishing port 9088 from the host to port 8088 in the container.  The container will be named ignition-test and use the 8.1.7 image.  Finally, the runtime arguments provided will set the Gateway name to docker-test with public address of localhost on HTTP port 9088 and HTTPS port 9043.

docker run -d -p 9088:8088 --name ignition-test inductiveautomation/ignition:8.1.7 \
    -n docker-test -a localhost -h 9088 -s 9043

Preserving Gateway State

When using containers, it is common for stateful applications (such as the Ignition Gateway) to leverage volumes to persist that state across image updates, container remove/create cycles, etc. This can be done by applying a named volume to the /usr/local/bin/ignition/data path within the container.  This is especially important if you need to make a change to your container configuration.  Since container configurations are immutable, the only way to change it is to stop/remove the old container and start a new one (with a new configuration).

Similar to the above, but this time with a named volume gw-data attached to /usr/local/bin/ignition/data within the container. If the volume doesn't already exist, it will be created automatically. Note the additional --pull option to make sure that the latest tag is always pulled before running--without this, the latest tag is only pulled if one isn't already present on your system.

docker run -d -p 9088:8088 --name ignition-test \
    -v gw-data:/usr/local/bin/ignition/data \
    --pull always inductiveautomation/ignition:latest \
    -n docker-test -a localhost -h 9088 -s 9043

By using named volumes, you're now able to stop and remove the ignition-test container and create a new one with a different configuration.  As long as you attach your volume, your gateway will start up with all of your tags and projects in their previous state.

Preserving KeyStores

Gateway Network Certificate

This PKCS #12 KeyStore contains the certificate and private key used for gateway network communications, and is created automatically on Gateway startup if not present. Typically this is maintained independently on a per-installation basis to avoid issues from operations such as gateway backup restorations. The situation within a container is somewhat different, and it is usually preferable to track this KeyStore with the rest of the gateway state preserved by a volume. Docker image now redirects, via sym-link, Gateway Network KeyStore creation from webserver/metro-keystore to data/local. This will allow the underlying image for the container to be upgraded without generating a new Gateway Network certificate (thus breaking existing approved certificates and connections).

SSL Configuration

When SSL is enabled on a Gateway, ssl.pfx is created as a PKCS #12 KeyStore with the private key, server certificate, and root/intermediate CA certificates. This file is automatically read by the Gateway on startup to enable SSL. Similar to the Gateway Network Certificate, this resides outside of the data/ volume since it is intended to persist across a gateway restore operation. Docker image now redirects, via sym-links, SSL KeyStore creation from webserver/ssl.pfx and webserver/csr.pfx to data/local. This allows a Docker container's SSL configuration to persist via the data volume without relying on extra bind-mounts. Disabling SSL now recognizes the presence of sym-links when removing the KeyStore and removes the final target of the link, leaving the sym-link in place. 

Automating the Restore of a Gateway Backup

To leverage this feature, bind-mount a gateway backup into the container and then use the -r runtime argument to specify the location and command the restore. Additionally, supply the ACCEPT_IGNITION_EULA=Y environment variable to accept the Ignition EULA (see the Licensing section below) and bypass that gateway commissioning step.

docker run -d -p 9088:8088 --name ignition-test \
    -v gw-data:/usr/local/bin/ignition/data \
    -v /path/to/gateway.gwbk:/restore.gwbk \
    -e ACCEPT_IGNITION_EULA=Y \
    inductiveautomation/ignition:8.1.7 \
    -n docker-test -a localhost -h 9088 -s 9043 \
    -r /restore.gwbk

Automate the Commissioning of a Fresh Gateway

docker run -d -p 9088:8088 --name ignition-test \
    -e ACCEPT_IGNITION_EULA=Y \
    -e GATEWAY_ADMIN_PASSWORD=password \
    -e IGNITION_EDITION=standard\
    inductiveautomation/ignition:8.1.8 \
    -n docker-test

Customizing JVM/Wrapper/Gateway Arguments on Container Launch

This example shows how to leverage the supplemental JVM/wrapper args feature. 

docker run -d -p 9088:8088 --name args-test \
    -e ACCEPT_IGNITION_EULA=Y \
	-e GATEWAY_ADMIN_PASSWORD=changeme \
    -e IGNITION_EDITION=standard\
    inductiveautomation/ignition:8.1.8 \
    -n args-test \
    -- wrapper.java.initmemory=256 -Dignition.allowunsignedmodules=true \
    -XX:MaxGCPauseMillis=200

docker run -d -p 9088:8088 --name ignition-test inductiveautomation/ignition:8.1.10 -n docker-test -a localhost -h 9088 -s 9043 \
   -- gateway.resolveHostNames=true gateway.useProxyForwardedHeader=true

Using Docker Compose

A common practice is to leverage Docker Compose to start your container and bundle the configuration with other services, such as databases and MQTT brokers.  Below is an example docker-compose.yml file that you can create inside of a new, empty folder.  The example below incorporates many of the configurability features mentioned in the various sections above.

# Docker Compose Example for inductiveautomation/ignition
# Compose Spec: https://github.com/compose-spec/compose-spec/blob/master/spec.md
---
services:
  # Ignition Gateway
  gateway:
    image: inductiveautomation/ignition:8.1.8
    ports:
      - 9088:8088
      - 9043:8043
    volumes:
      - gw-data:/usr/local/bin/ignition/data
    # env_file: ignition.env  # optionally specify variables in a file, or using `environment:` below
    environment:
      - ACCEPT_IGNITION_EULA=Y
      - GATEWAY_ADMIN_USERNAME=admin
      - GATEWAY_ADMIN_PASSWORD_FILE=/run/secrets/gateway-admin-password
      - IGNITION_EDITION=standard
      - TZ=America/Chicago  # see https://en.wikipedia.org/wiki/List_of_tz_database_time_zones#List
    secrets:
      - gateway-admin-password
    command: >
      -n docker-test
      -m 1024
      --
      wrapper.java.initmemory=512
      -Dignition.allowunsignedmodules=true

secrets:
  gateway-admin-password:
    file: secrets/GATEWAY_ADMIN_PASSWORD

volumes:
  gw-data:

Once defined, you can bring up the solution using `docker compose` commands.  See the animated example below:

Integrate Third-Party Modules After an Upgrade

When upgrading Ignition in Docker, third-party modules are not included with new images, so they will need to be re-installed. You can do this by creating a Docker derived image and use the derived image to copy these modules to the upgraded container.  The example below describes how to conduct a derived image build to integrate third-party modules. 

For this example, a module subfolder with the modules we are attempting to integrate will be labeled gw-build. The subfolder will also include a Dockerfile. The docker-compose.yml file needed for this process is located outside of this subfolder. We will be using a docker-compose.yml file similar to the previous example, but instead of using an image tag, we will be using a build tag. 

services:
  gateway:
    build:
	  context: gw-build
	  ## Specify the upstream version to derive from for the build argument in the Docker file.
	  args:
		IGNITION_VERSION: 8.1.28
    ports:
      - 8088:8088
    volumes:
      - gateway-data:/usr/local/bin/ignition/data
    environment:
      ACCEPT_IGNITION_EULA: "Y"
      GATEWAY_ADMIN_PASSWORD: password
      IGNITION_EDITION: standard
    command: >
      -n Ignition-supp-66195

volumes:
  gateway-data:

The Dockerfile within the gw-build folder will define the derived image by containing a build argument for the Ignition version. Notice this does not give a default version. This is because the version we want to build is specified and passed through our docker-compose definition. Next, we will add a command to copy the module files from this folder to the user-lib module folder inside the new Ignition image. 

ARG IGNITION_VERSION
FROM inductiveautomation/ignition:${IGNITION_VERSION}

COPY *.modl /usr/local/bin/ignition/user-lib/modules/

With these files defined, we can now run docker compose build to pull the image, perform all derived image build steps, and create the new image. 

User Migration

User Migration - Docker Compose

The following example uses Docker Compose to demonstrate how to migrate the container user and file ownership from the root user to a standard, non-elevated ignition user. If you are instead using the command line, see the next example for migrating users. Your environment may vary, depending on how your container is set up. This container is running Ignition version 8.1.25:

# User Migration Example (Docker Compose)
---
services:
  # Ignition Gateway
  gateway:
    image: inductiveautomation/ignition:8.1.25
    volumes:
      - ignition-data:/usr/local/bin/ignition/data
    ports:
      - 8088:8088
    command: >
      -n docker-test

volumes:
  ignition-data:

1. Upgrade the container to the latest version by changing the image tag to the version you want to upgrade to:

   User Migration Example (Docker Compose)

   # User Migration Example (Docker Compose)
   ---
   services:
     # Ignition Gateway
     gateway:
       image: inductiveautomation/ignition:8.1.26
       volumes:
         - ignition-data:/usr/local/bin/ignition/data
       ports:
         - 8088:8088
       command: >
         -n docker-test
   
   volumes:
     ignition-data:

2. Add the IGNITION_UID=2003 and IGNITION_GID=2003 environment variables to update the container permissions:

   User Migration Example (Docker Compose)

   # User Migration Example (Docker Compose)
   ---
   services:
     # Ignition Gateway
     gateway:
       image: inductiveautomation/ignition:8.1.26
       volumes:
         - ignition-data:/usr/local/bin/ignition/data
       ports:
         - 8088:8088
       environment:
         - IGNITION_UID=2003
         - IGNITION_GID=2003
       command: >
         -n docker-test
   
   volumes:
     ignition-data:

3. Declare the root user (user: "0:0"):

   User Migration Example (Docker Compose)

   # User Migration Example (Docker Compose)
   ---
   services:
     # Ignition Gateway
     gateway:
       image: inductiveautomation/ignition:8.1.26
       volumes:
         - ignition-data:/usr/local/bin/ignition/data
       ports:
         - 8088:8088
       environment:
         - IGNITION_UID=2003
         - IGNITION_GID=2003
       user: "0:0"
       command: >
         -n docker-test
   
   volumes:
     ignition-data:

4. Save the Docker Compose file, then run docker compose up -d.

   Note: By default, we are using the -d option in our Docker command. While you can also run the command without -d, the -d option runs the container in detached mode, allowing the container to run in the background even after closing the terminal.

5. The container will now use the root user when it starts up, but will launch Ignition as a standard ignition user. All of the files in the ignition-data volume have the proper ownership. We can now remove the IGNITION_UID and IGNITION_GID environment variables and the user:"0:0" override:

   User Migration Example (Docker Compose)

   # User Migration Example (Docker Compose)
   ---
   services:
     # Ignition Gateway
     gateway:
       image: inductiveautomation/ignition:8.1.26
       volumes:
         - ignition-data:/usr/local/bin/ignition/data
       ports:
         - 8088:8088
       command: >
         -n docker-test
   
   volumes:
     ignition-data:

6. Finally, we can rerun the docker compose up -d command to recreate the container. Since we removed the environment variables and updated container permissions, the container will launch with the default user being a standard ignition user.
   
   
7. To check if the user successfully migrated over, we see the process listing and who the user is for each process using the command docker compose exec gateway ps aux in the terminal. Additionally, you can use the command docker compose exec gateway whoami to see who the default user for the container is:
   

User Migration - Command Line

The following example uses the command line to demonstrate how to migrate the container user and file ownership from the root user to a standard, non-elevated ignition user. If you are instead using Docker Compose, see the preceding example. Your environment may vary, depending on how your container is set up. The following container is called example-gw and is running Ignition version 8.1.25:

docker run --name example-gw -v example-gw-data:/usr/local/bin/ignition/data \
    -e IGNITION_EDITION=standard -e ACCEPT_IGNITION_EULA=Y -e GATEWAY_ADMIN_PASSWORD=password \
    -p 8088:8088 \
    inductiveautomation/ignition:8.1.25 \
    -n example-gw

1. Stop and remove your Docker container using the following commands. Keep in mind that you will need to replace example-gw with your container name:

   User Migration Example (Command Line)

   # Stop and remove container
   docker stop example-gw
   docker rm example-gw

2. Modify the container run configuration to declare the root user using --user 0:0 (The UID and GID will both be 0):

   User Migration Example (Command Line)

   # Declare the root user
   docker run --name example-gw --rm -v example-gw-data:/usr/local/bin/ignition/data \
       -p 8088:8088 \
       --user 0:0 \
       inductiveautomation/ignition:8.1.25 \
       -n example-gw

3. Update the container permissions by adding the IGNITION_UID and IGNITION_GID environment variables. You can do this by adding -e IGNITION_UID=2003 -e IGNITION_GID=2003 after --user 0:0:

   User Migration Example (Command Line)

   # Update the container permissions
   docker run --name example-gw --rm -v example-gw-data:/usr/local/bin/ignition/data \
       -p 8088:8088 \
       --user 0:0 -e IGNITION_UID=2003 -e IGNITION_GID=2003 \
       inductiveautomation/ignition:8.1.25 \
       -n example-gw

4. The container's Gateway should now be running under a standard ignition user, using a UID of 2003 and a GID of 2003. You can run the following command to count the number of processes running as a standard ignition user:

   User Migration Example (Command Line)

   # Count the number of running processes under the ignition user
   docker exec example-gw pgrep -u 2003 -c

   Note: 

   There should be 3 processes:

   • the entrypoint
   • the Java wrapper
   • the Java process

5. File ownership should now also belong to the standard ignition user. You can use the following command to verify that there are no files owned by any other user aside from the standard ignition user:

   User Migration Example (Command Line)

   # Verify file ownership
   docker exec example-gw bash -c "find /usr/local/bin/ignition ! -user 2003 | wc -l"

6. Once you have verified file ownership and the user the processes are running under, you can now recreate the container against the new image with the default ignition user (UID = 2003) and update your Gateway to the latest version:

   User Migration Example (Command Line)

   # Recreate the container
   docker stop example-gw
   docker rm example-gw
   docker run --name example-gw --rm -v example-gw-data:/usr/local/bin/ignition/data \
       -p 8088:8088 \
       inductiveautomation/ignition:8.1.<new> \
       -n example-gw

Licensing

The Inductive Automation software contained in this Docker container image is licensed under the terms of the Inductive Automation Software License Agreement.

By passing the value ACCEPT_IGNITION_EULA=Y, you agree that your use of Inductive Automation software running in this Docker container image is governed by the terms of the Inductive Automation Software License Agreement.

All third party software (whether open or closed) running in this Docker container image is licensed as indicated in this Docker Hub “License” section or in the container itself, usually as a NOTICE or LICENSE file. You agree to comply with any relevant licenses for third party software contained in this Docker container image.