Available Control Center Information

The Notifications area of your dashboard displays useful information and alerts. For example, information if a client drops a message. An alert does not necessarily mean that something is wrong. However, an alert can indicate that an unwanted behaviour has occurred.

Example notification area with connection-limit alert:

Example notification area with no connected clients that displays useful links:

The Active License Information card on your control center dashboard displays key information about the HiveMQ license that is currently in use.

Based on the maximum number CPU cores the active licence allows, the cores status bar shows the current CPU capacity of the selected node:

A green bar indicates that less than 75% of the CPU cores that the active license allows are in use.

A yellow bar indicates that more than 75% of the CPU cores that the active license allows are in use.

A red bar indicates that more than 90% of the CPU cores that the active license allows are in use.

The statistics area of your control center dashboard shows information for each individual node in your cluster. Nodes are identified with a randomly-generated cluster node ID. An asterisk (*) after the cluster node ID indicates the node that is used for the HiveMQ control-center connection.

To view statistics for a node, select the node ID.

The following metrics are available for each node in the cluster:

HiveMQ uses cluster-wide snapshots to display all available MQTT sessions. To view information for the MQTT sessions that are currently available, you need to create a fresh snapshot. The HiveMQ snapshot offers a consolidated view of all nodes in your cluster at a particular point in time. This unified snapshot provides an efficient way to sort, filter, and navigate through all available MQTT sessions.

To create a snapshot, select Refresh Snapshot. Based on the number of MQTT sessions on your cluster, the refresh process can take a few moments. When the process finishes, an overview table of the current clients displays.

To change the order in which clients are sorted on the overview, click the column header.

To filter clients by client ID, username, or IP address, select the desired option from the drop-down menus in the Clean Session and Connected columns.

The sorting options and filters that you apply to the Clients overview table are stored until you log out.
If you leave the Clients overview and return later, the filters and sorting options that you applied to the overview table remain active.

To open the Client Detail page of a client and access additional client actions, select the identifier of the client on the overview.

This page displays when you select a client identifier in the Clients overview.
The client identifier and the connection status of the client for which details are shown appears at the top of the page.

The Prev and Next options on your client detail pages allow you to easily navigate through the clients on your Clients overview.

Prev displays information for the client one row before the currently selected entry in the overview table.
Next displays information for the client one row after the currently selected entry in the overview table.

If you change the sorting order or filters of your Clients overview table, the changes that you make are immediately reflected in the Prev and Next information.

To view more information about each item that is shown on the details page, select the question mark next to the desired column.

For example, more information on sessions:

The Shared Subscriptions overview provides basic information for each shared subscription on your HiveMQ cluster.

HiveMQ uses cluster-wide snapshots to display all available shared subscriptions. To view information for the shared subscriptions that are currently available, you need to create a fresh snapshot. The HiveMQ snapshot offers a consolidated view of all nodes in your cluster at a particular point in time. This unified snapshot provides an efficient way to sort, filter, and navigate through all of the available MQTT sessions.

To create a snapshot, select Refresh Snapshot. Based on the number of shared subscriptions on your cluster, the refresh process can take a few moments. When the process finishes, an overview table of your current shared subscriptions displays.

To change the order in which the data is sorted on the overview, click the column header. To filter for a specific shared subscription, enter the desired topic in the Topic field.

The sorting options and filters that you apply to the overview table are stored until you log out. If you leave the overview and return later, the filters and sorting options that you applied remain active.

This page displays when you select a topic in the Shared Subscriptions overview.
The shared subscription topic for which details are shown appears at the top of the page.

To view more information about an item on the details page, click the question mark next to the desired column.

For example, more information about shared subscription client details:

The Prev and Next options on your detail pages allow you to easily navigate through entries and respect the filters and sorting options that you apply to the overview table.

Prev: Displays information for the subscription one row before the currently selected entry in the overview table.
Next: Displays information for the subscription one row after the currently selected entry in the overview table.

When you change the sorting order or filters of your Shared Subscription overview, your changes are immediately reflected in the Prev and Next information of your detailed view.

HiveMQ uses cluster-wide snapshots to display all available retained messages. To view information for the retained messages that are currently available, you need to create a fresh snapshot. The HiveMQ snapshot gives you a consolidated view of all nodes in your cluster at a particular point in time. This unified snapshot provides an efficient way to sort, filter, and navigate through all retained messages that are available on your cluster.

To create a snapshot, select Refresh Snapshot. Based on the number of retained messages that are available in your cluster, the refresh process can take a few moments. When the process finishes, an overview table of the retained messages displays.

To change the order in which the data is sorted on the overview, click the column header. To filter the messages that are displayed by topic, enter the desired topic in the input field of the Topic column.

The sorting options and filters that you apply to the retained messages overview table are stored until you log out. If you leave the retained messages overview and return later, the filters and sorting options that you applied to the overview table remain active.

This page displays when you select the topic of a retained message in the Retained Messages overview. The topic of the retained message for which details are shown appears at the top of the page.

Prev and Next options on each detail page allow you to easily navigate through the retained messages that are listed on your retained messages overview table.

Prev displays detailed information for the message one row before the currently selected entry in the overview table.
Next displays detailed information for the message one row after the currently selected entry in the overview table.

If you change the sorting order or filters on the Retained Messages overview table, the changes are immediately reflected in the Prev and Next information.

The Retained Message Detail page provides message information and user property information for the retained message that is currently selected.

To view more information for items shown on the details page, select the question mark next to the desired column.

The Data Hub dashboard provides a clear overview of the current quality of your data pipelines.

The visualizations and client list on the dashboard can help you quickly understand the state of your data pipelines and act to resolve issues with problematic clients efficiently:

For detailed information on Data Hub features and configuration options, see HiveMQ Data Hub.

HiveMQ Modules for Data Hub offer easy-to-use functionality that can be quickly accessed from the HiveMQ Control Center. Modules can be used to define fine-grained and fully flexible Data Hub policies or to utilize pre-defined modules that implement pre-defined functionality.

The Modules overview provides basic information for each module on your HiveMQ cluster and quick access to Import Custom Modules you have built into your HiveMQ Modules for Data Hub deployment.

To update information on the overview to the most current stand, select Refresh Modules.
When you filter or sort information on the overview, the overview automatically refreshes.

For more information on the use of modules in HiveMQ Data Hub, see HiveMQ Modules for Data Hub.

Schemas are an essential part of data policies. Your Data Hub schemas define the rules and constraints that MQTT payload data must adhere to. These constraints help to ensure data quality and to maintain the integrity of your HiveMQ deployment.
Data Hub currently supports JSON Schemas and Protobuf.
For more information on the use of schemas in HiveMQ Data Hub, see Schemas.

The Schemas overview provides basic information for each schema on your HiveMQ cluster.

HiveMQ uses cluster-wide snapshots to display all available schemas. To view information for the schemas that are currently available, you need to create a fresh snapshot. The HiveMQ snapshot offers a consolidated view of all nodes in your cluster at a particular point in time. This unified snapshot provides an efficient way to sort, filter, and navigate through all available schemas.

To take a new snapshot, select Refresh Snapshot.
When you filter or sort the information on the overview, the snapshot automatically updates.

To create a new schema, select Add New Schema. For more information see, Schema Detail - Create Schema.

To view and manage an existing schema, select the name of the schema in the Schemas overview. For more information, see Schema Detail -View Schema Details

The Schema Detail - Create Schema page displays when you select the Add New Schema option on the Schemas overview. Here, you can create and save new schemas:

The options and help text automatically adjust based on your configuration choices. For example, the creation of a JSON Schema requires a Schema ID and a Schema Definition and the creation of a Protobuf schema requires a Schema ID, Schema Definition, and a Message Type.

For detailed information on the configuration and use of schemas in Data Hub, see Data Hub Schemas.

The Schema Detail - for Schema ID page displays when you select an existing schema on the Schemas overview. Here, you can add new schema versions, download schema versions, or delete all versions of the selected schema:

IoT devices can send a wide range of data sets. As a result, the MQTT data you receive often contains diverse data points, formats, and units. Data transformation scripting with JavaScript can help you bring diverse data into a common format that an application can understand and process.

The HiveMQ 4.23 platform release introduced the Early Access Preview (EAP) version of the new Data Hub data transformation functionality. Our transformations feature gives you the ability to add custom JavaScript-based transformation functions to Data Hub data policies. For more information on the use of JavaScript scripting in Data Hub see, Transformations.

HiveMQ uses cluster-wide snapshots to display all available scripts. To view information for the scripts that are currently available, create a fresh snapshot. The HiveMQ snapshot offers a consolidated view of all scripts in your cluster at a particular point in time. This unified snapshot provides an efficient way to sort, filter, and navigate through all available scripts.

To take a new snapshot, select Refresh Snapshot.
When you filter or sort the information on the overview, the snapshot automatically updates.

To create a new script, select Add New Script. For more information see, Script Detail - Create Script.

To view and manage an existing schema, select the name of the schema in the Script overview. For more information, see Script Detail -View Script Details

The Script Detail - Create Script page displays when you select the Add New Script option on the Script overview. Here, you can create and save new scripts:

To save your script, select Save Script.

The Script Detail - for Script ID page displays when you select an existing script on the Script overview. Here, you can add new script versions, download script versions, or delete all versions of the selected script:

The Referencing Data Polices area of the detail lists and links to all data policies that use the script.

You can create and manage two types of policies on the control center: data policies and behavior policies.

Data Hub data policies ensure that the payload data in MQTT messages has the structure and format you expect. Data Policies use schema-based data validation to verify that MQTT data meets your requirements.

The Data Policies overview provides basic information for each data policy on your HiveMQ cluster.

HiveMQ uses cluster-wide snapshots to display all available data policies. To view information for the data policies that are currently available, you need to create a fresh snapshot. The HiveMQ snapshot offers a consolidated view of all nodes in your cluster at a particular point in time. This unified snapshot provides an efficient way to sort, filter, and navigate through all available data policies.

To take a new snapshot, select Refresh Snapshot.
Based on the number of data policies on your cluster, the refresh process can take a few moments.
When you filter or sort the information on the overview, the snapshot automatically updates.

To create a new data policy, select Add New Policy.

To view the Data Policy Detail for an existing data policy, select the name of the policy on the Data Policies overview.

On the Data Policy Detail of an existing policy, you can view, edit, download, or create a module from the data policy.

The Create Policy view of the Data Policy Detail displays when you select the Add New Data Policy option on the Data Policies overview.

The tabs on Data Policy Detail | Create Policy view guide you through the policy creation process from the selection of validators to the configuration of actions the validation outcomes can trigger.

For detailed configuration information and examples, see Data Hub Data Policies

Required fields are marked with an *. To save the policy, all required fields must be completed. You can save your policy at any time or switch to the Summary tab to review the policy before you save.

The Summary page of the Data Policy Detail allows you to review, edit, save, or delete your data policy. The summary information includes links to all schemas and scripts that are associated with the selected policy.

To save the data policy and return to the Data Policies overview, select Save Policy. To close the Summary and return to the Data Policies overview, select Cancel.

You can create and manage two types of policies on the control center: data policies and behavior policies.

Data Hub behavior policies give you the ability to model the behavior of your MQTT clients throughout the entire lifecycle of the client.
Client behavior is checked against your defined behavior model to determine whether the client is acting in the expected manner. The behavior model builds a level of control on top of the MQTT protocol with a state machine that checks how the client works with the HiveMQ broker.

For more information on the use of behavior policies in HiveMQ Data Hub, see Behavior Policies.

The Behavior Policies overview provides basic information for each behavior policy on your HiveMQ cluster.

HiveMQ uses cluster-wide snapshots to display all available behavior policies. To view information for the behavior policies that are currently available, you need to create a fresh snapshot. The HiveMQ snapshot offers a consolidated view of all nodes in your cluster at a particular point in time. This unified snapshot provides an efficient way to sort, filter, and navigate through all available behavior policies.

To take a new snapshot, select Refresh Snapshot.
When you filter or sort the information on the overview, the snapshot automatically updates. Based on the number of behavior policies on your cluster, the refresh process can take a few moments.

To create a new behavior policy, select Add New Policy.

The Behavior Policy Detail displays when you select the Add New Policy option on the Behavior Policies overview.

The tabs of the Behavior Policy Detail guide you through the policy creation process from defining for which clients the policy applies to defining actions that the transitions in the state of the client trigger.

For detailed configuration information and examples, see Data Hub Behavior Policies

Required fields are marked with an *. To save the policy, all required fields must be completed. You can save your policy at any time or switch to the Summary tab to review the policy before you save.

The Summary page of the Data Policy Detail allows you to review, edit, save, or delete your data policy at any time. To close the Summary and return to the Behavior Policies overview, select Cancel.

The Active License area of the control center Licenses view provides detailed information on the HiveMQ license that is currently in use. Only one license can be active at a time.

The Active License overview provides detailed information on the license that is in use.

If no license is installed in the license folder of your HiveMQ installation, HiveMQ automatically uses a free trial license. Trial licenses are limited to 25 concurrent connections:

To view a list of the features the trial license includes, expand the Show Features area:

If your license expires, a trial license is used automatically. Information on the expired license appears in the Inactive Licenses area.