Multi Instance Framework Hermes

Learn how messages are produced and consumed in Hermes during normal operation, Advanced High Availability (AHA) transfer, and failover scenarios.

The Hermes Settings page is a centralized interface that enables Hermes administrators and maintenance users to monitor and control the configuration properties that govern the Hermes Messaging Service.

To clone your database from one instance to another successfully with Hermes enabled, you must ensure that certain Hermes tables are preserved and excluded. The list of tables in the preserve list should match those in the exclude list and vice versa.

Learn how the Hermes Messaging Service is activated. Set up a secure connection to the Hermes Messaging Service.

Consume test messages from a Hermes topic by configuring two consumer clients.

Receive a notification when an attempt to access Hermes is received from an unauthorized IP address.

Create a topic for sending and receiving test messages in the Hermes Kafka cluster.

Organize your Kafka topics by creating a namespace.

Create a topic from within ServiceNow. Creating a topic from your instance adds a topic record to the Kafka Topics [sys_kafka_topic] table and adds a Kafka topic to Hermes.

Prevent topics from being added to a namespace by deleting the namespace in Hermes.

Remove a topic and its messages by deleting it from Hermes. Deleting a topic record deletes it from your instance and from the Hermes Kafka cluster.

Enable encryption at rest on a Hermes topic to help protect message data stored on broker disks from unauthorized access.

Encryption at rest for Hermes topics protects message data stored on broker disks from unauthorized access. Hermes supports both ServiceNow-managed keys and keys you provide using the Bring Your Own Key (BYOK) model.

Produce and consume Kafka messages in your ServiceNow instance using the Hermes Messaging Service.

Learn about the Hermes Messaging Service and how it helps you manage the flow of data between your Kafka environment and your instance.

The Hermes Messaging Service is not a standalone plugin.

Monitor the Hermes Messaging Service by viewing diagnostics and inspecting topics.

The Hermes Messaging Service architecture is built on the following components.

If any conkeyrefs are broken, re-add them from the doc/source/reuse/domain-separation/domain-separation-overview.dita file.In the short description, edit the first sentence to state whether domain separation is supported or not and add the application name. Keep the conkeyref at the end that describes domain separation.Domain separation is supported for the Hermes Messaging Service. Domain separation enables you to separate data, processes, and administrative tasks into logical groupings called domains. You can control several aspects of this separation, including which users can see and access data.

These system properties control the behavior of the Hermes Messaging Service.

Reference topics provide details on the Hermes Messaging Service components and the security model.

Hermes Messaging Service is installed with these roles.

The Hermes Messaging Service security model relies on the following capabilities.

The Hermes Messaging Service enables you to integrate your Apache Kafka environment with your ServiceNow instance.

Manage background jobs in Hermes Messaging Service to control when and how often scheduled tasks run. You can make a job inactive, re-enable it, or adjust its interval from the Hermes Settings page.

View, modify, and manage configuration properties that control the behavior of Hermes Messaging Service. You can update property values, manage background job states, or adjust settings where automated detection is unavailable.

Group Kafka topics together for simplified topic management and access control specification using namespaces.

Organize and manage namespaces and topics in the Hermes Kafka cluster using the Hermes Messaging Service.

Manage topic records in your instance and Kafka topics in the Hermes Kafka cluster using the Hermes Messaging Service.

Monitor the amount of data produced to and consumed from the Hermes cluster over time. Use the Hermes Usage Dashboard to track data inflow and outflow by topic, application, and time period.

Monitor message processing and view topics in the Hermes Kafka cluster that belong to you using the Hermes Messaging Service topic inspector.

Install the Apache Kafka binaries on your Unix or Windows client machine.

Produce test messages to a Hermes topic by configuring a producer client.

Learn how to produce and consume messages to Hermes from a Kafka client.

Synchronize topic records in your instance with topics in the Hermes Kafka cluster by rescanning.

Restrict access to Hermes by IP address.

Revoke a ServiceNow instance-signed certificate so that it can't be used in secure connections to the Hermes Messaging Service.

Check the status of and test the connection to the Hermes Kafka cluster by sending and receiving test messages.

Secure your Kafka topics by generating a ServiceNow instance-signed certificate.

Message usage through the Hermes Messaging Service is tracked for monitoring and management purposes through the Kafka topic name.

Update a Kafka topic in Hermes by modifying the topic record.

Review and modify the current the Hermes configuration properties to control Apache Kafka integration, topic management, and other messaging behavior.

Review Hermes event details by viewing log messages.

View the payload of a message in a Hermes topic using the Hermes Messaging Service topic inspector.