Pulling an Agent Image

Pull the version of  the Agent image that corresponds to the JS7 release in use:

docker image pull sosberlin/jobscheduler:agent-2-0-0

Running an Agent Container

After pulling the Agent image you can run the container with a number of options like this:

#!/bin/sh

docker run -dit --rm \
      --user="$(id -u $USER):$(id -g $USER)" \
      --hostname=js7-agent-2-0-primary \
      --network=js7 \
      --publish=14445:4445 \
      --env="RUN_JS_HTTP_PORT=14445" \
      --env="RUN_JS_JAVA_OPTIONS=-Xmx256m" \
      --mount="type=volume,src=js7-agent-2-0-primary-config,dst=/var/sos-berlin.com/js7/agent/var_4445/config" \
      --mount="type=volume,src=js7-agent-2-0-primary-logs,dst=/var/sos-berlin.com/js7/agent/var_4445/logs" \
      --mount="type=volume,src=js7-agent-2-0-primary-state,dst=/var/sos-berlin.com/js7/agent/var_4445/state" \
      --name js7-agent-2-0-0-primary \
      sosberlin/jobscheduler:agent-2-0-0

Explanations:

• --user Inside the container the Agent is operated for the user account jobscheduler. In order to access e.g. log files created by the Agent that are mounted to the Docker host it is recommended that you map the account that is starting the container to the jobscheduler account inside the container. The --user option accepts the user ID and group ID of the account that will be mapped. The above example makes use of the current user.
• --network The above example makes use of a Docker network - created e.g. with docker network create js7 - to allow network sharing between containers. Consider that any inside ports used by Docker containers are visible within a Docker network. Therefore an Agent running for the inside port 4445 is accessible from the container's hostname and the same port within the Docker network.
• --publish The Agent is prepared to listen to the HTTP port 4445. An outside port of the Docker host can be mapped to the Agent's inside HTTP port. This is not required for use with a Docker network, see --network, however, it will allow to directly access the Agent from the Docker host by its outside port .
• --env=RUN_JS_HTTP_PORT Consider to specify the same outside port that is used with the --publish option to map an outside port to the inside HTTP port.
• --env=JAVA_OPTIONS This allows to inject any Java options to the Agent's container. Preferably this is used to specify memory requirements of an Agent, e.g. with -Xmx256m.
• --mount The following volume mounts are suggested:
  • config: The optional configuration folder allows to specify individual settings for Agent operation, see below and JS7 - Agent Configuration. Without this folder the default settings are used.
  • logs: In order to have Agent log files persisted they should 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 Agent requires a directory for journal information that should be persisted. The journal is required to restore the state of orders when restarting the Agent.

Configuring an Agent

Consider that it is not required to configure an Agent - it runs out-of-the-box. Zero configuration includes that

• deployment of objects, e.g. workflows and jobs, is not subject to compliance requirements such as non-repudiation.
• HTTP connections are used that expose unencrypted communication between Controller and Agent and that are secured by hashed passwords.

Users who intend to operate a compliant and secure job scheduling environment should consider the explanations for

• deployment of objects with digital signatures that can be used to restrict and to verify who deploys a given object such as a workflow.
• HTTPS connections that encrypt communication and that include mutual authentication by certificates without use of passwords.

Compliance: Use of Signing Certificates

Agents accept deployments for a number of objects such as workflows from a Controller only if such objects are digitally signed.

• If JOC Cockpit is operated for Security Level Low then a single X.509 private key assigned to the root account is used to sign any objects by any JOC Cockpit accounts.
• If JOC Cockpit is operated for Security Level Medium or High then each account that deploys objects has to own an individual X.509 key or PGP key.

To verify the signature of an object the Agent has to apply the public key or certificate that matches the private key used for signing with JOC Cockpit.

• If X.509 private keys are used for signing of objects then the Root CA Certificate or Intermediate CA Certificate that was used to sign the respective private key has to be in place with the Agent.
• If PGP private keys are used for signing of objects then the public key matching the signing key has to be in place with the Agent.
• The Agent expects certificates/public keys from the following locations:
  • X.509 Certificates
    • Location
      • Windows: C:\ProgramData\sos-berlin.com\js7\agent\var_4445\config\private\trusted-x509-keys
      • Unix: /var/sos-berlin.com/js7/agent/var_4445/config/private/trusted-x509-keys
    • The expected X.509 certificate format is PEM. Certificates can be added from any file names with the extension .pem.
    • Consider that instead of individual certificates per signing key the Root CA Certificate or Intermediate CA Certificate that was used to sign the private keys is sufficient.
  • PGP Public Keys
    • Location
      • Windows: C:\ProgramData\sos-berlin.com\js7\agent\var_4445\config\private\trusted-pgp-keys
      • Unix: /var/sos-berlin.com/js7/agent/var_4445/config/private/trusted-pgp-keys
    • PGP public keys are expected in ASCII armored format. They can be added from any file names with the extension .asc.
    • Consider that for each PGP private key that is used for signing the corresponding public key has to be available with the Agent.
  • By default the Agent ships with an X.509 certificate of SOS that matches the default signing key available with the root account in JOC Cockpit.
• In order to add individual certificates/public keys add the respective files to the above location corresponding the key type. To revoke certificates/public keys accordingly remove the respective files from the above location matching the key type.
• The above locations for certificates/public keys can be accessed from the Docker volume specified with the --mount option for the Agent's container directory /var/sos-berlin.com/js7/agent/var_4445/config. The locations for X.509 certificates and PGP public keys are available from sub-directories.

Security: Use with HTTPS Connections

The Agent by default is prepared for connections by Controllers using the HTTP and the HTTPS protocols. 

In order to activate HTTPS consider the following prerequisites.

Provide Keystore, Truststore and Configuration for Mutual Authentication

Connections to Agents are established from a Controller. If the HTTPS protocol is used then in addition to securing the communication channel the Agent requires mutual authentication.

Agent Keystore and Truststore

• The Controller's private key has to be created for Server Authentication and Client Authentication extended key usages.
• The Agent is provided
  • a keystore that holds its private key, certificate, Root CA Certificate and optionally Intermediate CA Certificate.
  • a truststore that holds the certificate chain - consisting of Root CA Certificate and optionally Intermediate CA Certificate - required to verify the Controller's certificate.
• Keystores and truststores are files in PKCS12 format, usually with a .p12 extension. They should be added to the following locations:
  • Keystore
    • Windows: C:\ProgramData\sos-berlin.com\js7\agent\var_4445\config\private\https-keystore.p12
    • Unix: /var/sos-berlin.com/js7/agent/var_4445/config/private/https-keystore.p12
  • Truststore
    • Windows: C:\ProgramData\sos-berlin.com\js7\agent\var_4445\config\private\https-truststore.p12
    • Unix: /var/sos-berlin.com/js7/agent/var_4445/config/private/https-truststore.p12

Agent Configuration

• The Agent's private.conf configuration file has to be added the following configuration items. For details see JS7 - Agent Configuration
  • Mutual Authentication
    • Agent Configuration for Mutual Authentication

      js7 {
          auth {
              # User accounts for https connections
              users {
                  # Controller account for connections by primary/secondary Controller instance
                  Controller {
                      distinguished-names=[
                          "DNQ=SOS CA, CN=js7-controller-primary, OU=IT, O=SOS, L=Berlin, ST=Berlin, C=DE",
                          "DNQ=SOS CA, CN=js7-controller-secondary, OU=IT, O=SOS, L=Berlin, ST=Berlin, C=DE"
                      ]
                  }
              }
          }

    • This setting specifies the distinguished names that are available from the subjects of Controller certificates. Consider that the common name (CN) attribute specifies the hostname of a Controller. The configuration authenticates a given Controller as the distinguished name is unique for a server certificate and therefore replaces use of passwords.
  • Keystore and truststore locations:
    • Agent Configuration for Keystore and Truststore Locations

      js7 {
          web {
              # Locations of keystore and truststore files for HTTPS connections
              https {
                  keystore {
                      # Default: ${js7.config-directory}"/private/https-keystore.p12"
                      file=${js7.config-directory}"/private/https-keystore.p12"
                      key-password=jobscheduler
                      store-password=jobscheduler
                  }
                  truststores=[
                      {
                          # Default: ${js7.config-directory}"/private/https-truststore.p12"
                          file=${js7.config-directory}"/private/https-truststore.p12"
                          store-password=jobscheduler
                      }
                  ]
              }
          }
      }

    • The above configuration items specify the locations of keystore and truststore.
    • Consider optional use of a key password and store password for keystores and of a store password for truststores.

Run Agent Container for HTTPS Connections

The following additional arguments are required for HTTPS connections:

#!/bin/sh

docker run -dit --rm \
      ...
      --publish=14443:4443 \
      --env="RUN_JS_HTTPS_PORT=14443" \
      ...

Explanations:

• --publish The Agent image is prepared to accept HTTPS requests on port 4443. If the Agent is not operated in a Docker network then an outside port of the Docker host has to be mapped to the inside HTTPS port 4443. The same port has to be assigned the RUN_JS_HTTPS_PORT environment variable.
• --env=RUN_JS_HTTPS_PORT The port assigned this environment variable is the same as the outside HTTP port specified with the --publish option.

Note:

• When using HTTPS then consider to drop the HTTP port of the Agent by omitting the following above settings:
  • --publish=14445:4445 This mapping should be dropped in order to prevent incoming traffic to the Agent's HTTP port.
  • --env=RUN_JS_HTTP_PORT Without this setting the Agent will not listen to an HTTP port.