Introduction

• The JS7 Controller comes preinstalled from a container image.
• Initial operation for JS7 Controllers includes:
  
  • registering the Controller instance(s) and Agents that are used in the job scheduling environment.
  • optionally registering a JS7 Controller Cluster. 

As an alternative to the instructions from this article users can refer to the JS7 - Controller Installation using Docker Compose article.

Installation Video

This video explains how to install the JS7 Controller for containers:

Pulling the Controller Image

Pull the version of the Controller container image that corresponds to the JS7 release in use, for example:

docker image pull sosberlin/js7:controller-2-5-0

Note: Current releases should be applied as available from https://hub.docker.com/r/sosberlin/js7

Running the Controller Container

After pulling the Controller image you can run the container with a number of options such as:

#!/bin/sh

docker run -dit --rm \
      --hostname=js7-controller-primary \
      --network=js7 \
      --publish=15444:4444 \
      --env="RUN_JS_JAVA_OPTIONS=-Xmx256m" \
      --env="RUN_JS_ID=jobscheduler" \
      --env="RUN_JS_USER_ID=$(id -u $USER):$(id -g $USER)" \
      --mount="type=volume,src=js7-controller-primary-var,dst=/var/sos-berlin.com/js7/controller/var" \
      --name js7-controller-primary \
      sosberlin/js7:controller-2-5-0

Explanation:

• --network The above example makes use of a container network - created with the docker network create js7 command - to allow network sharing between containers. Note that any inside ports used by containers is visible within a container network. Therefore a Controller instance running for the inside port 4444 can be accessed using the container's hostname and the same port within the container network.
• --publish The Controller is prepared to listen to the HTTP port 4444. An outside port of the container's host can be mapped to the Controller's inside HTTP port. This is not required for use with a container network, see --network, however, it will allow direct access to the Controller from the container's host through its outside port .
• --env=RUN_JS_JAVA_OPTIONS This allows to Java options to be injected into the Controller's container. Preferably this is used to specify memory requirements of a Controller, e.g. with -Xmx256m.
• --env=RUN_JS_ID This setting specifies the Controller ID that is a unique identifier for either a standalone Controller instance or for both the primary and secondary Controller instances in a cluster that use a common Controller ID.
• --env=RUN_JS_USER_ID Inside the container the Controller is operated with the jobscheduler user account. In order to access, for example, log files created by the Controller and mounted to the container's host, it is recommended that you map the account that starts the container to the jobscheduler account inside the container. The RUN_JS_USER_ID environment variable accepts the User ID and Group ID of the account that will be mapped. The example listed above uses the current user, for details see JS7 - Running Containers for User Accounts.
• --mount The following volume mounts are suggested:
  • var: This folder works as an entry point to the following sub-folders:
    • config: The configuration folder allows the specification of  individual settings for the operation of the Controller - see the sections below and the JS7 - Controller Configuration Items article. Default settings are available from initial operation..
    • logs: In order to have persistent Controller log files they have to be written to a volume that is mounted for the container. Feel free to adjust the volume name from the src attribute, however, the value of the dst attribute should not be changed as it reflects the directory hierarchy inside the container.
    • state: The Controller requires a directory for journal information that should be persistent. The journal is required to restore the state of orders when restarting the Controller.

  • Containers offer a number of ways of mounting volumes, which include, for example, creating a local folder and mapping the folder to a volume before executing the docker run command listed above:

    Example how to create Docker volumes

    # example to map volumes to directories on the container's host prior to running the Controller container
    mkdir -p /home/sos/js7/js7-controller-primary/var
    docker volume create --driver local --opt o=bind --opt type=none --opt device="/home/sos/js7/js7-controller-primary/var" js7-controller-primary-var

Time Service

It is important that a time service is operated on the container's host which runs the Controller in order to synchronize the system clock's time.

Log Files

Access to log files is essential for identifying problems during installation and operation of containers.

When mounting a volume for log files as explained above you should have access to the files indicated in the JS7 - Log Files and Locations article.

• The controller.log file reports general information, warnings and errors.
• The watchdog.log file includes information about automated restarts of the Controller.

Initial Operation

The following information applies for use of the Controller with the Open Source license and with the commercial JS7 - License:

• JS7 - Initial Operation for Standalone Controller
• JS7 - Management of Standalone Controllers

The following information applies if the Controller is used for high availability in a JS7 - Controller Cluster using the commercial JS7 - License:

• JS7 - Initial Operation for Controller Cluster
• JS7 - Management of Controller Clusters

Further Resources

Configure the Controller

Note that it is not necessary to configure the Controller - it runs out-of-the-box. The default configuration specifies that:

• deployment of objects such as workflows and jobs is not subject to compliance requirements such as non-repudiation.
• HTTP connections are used which expose unencrypted communication between JOC Cockpit and Controller. Authentication is performed by hashed passwords.

Users who intend to operate a compliant and secure job scheduling environment or who wish to operate the Controller as a cluster for high availability are recommended to familiarize themselves with the JS7 - Controller Configuration for Containers article series.

Build the Controller Image

User who wish to create individual images of the Controller will find instructions in the JS7 - Controller Build of Container Image article.