The HiveMQ Control center at a glance
Written by Margaretha Erber
Published: July 1, 2019
At HiveMQ we know that HiveMQ is a business critical and central component in our customers’ production deployments. For these kinds of deployments it’s necessary to have a simple and quick overview of the health of the cluster and the MQTT deployment itself.
To solve these needs in an efficient and easy way we decided to equip HiveMQ with a prebuilt solution: the HiveMQ Control Center.
The HiveMQ Control Center is a good starting point to get cluster-wide insights into the HiveMQ deployment. It works with millions of connected MQTT clients and delivers a fast and efficient overview of the MQTT deployment. It is especially helpful in finding a needle in a haystack as it gives you the possibility to drill down into the details of your deployment. With its intuitive and simple interface, the Control Center also allows you to perform cluster-wide administrative actions without having access to the systems on which HiveMQ is running.
Cluster Metrics on the Dashboard
To get started, the HiveMQ Control Center Dashboard provides an overview of the cluster health and insights on the most pressing issues at a glance. With its seven simple built-in key metrics it enables administrators to monitor the current MQTT message throughput and usage of the cluster without the need of a third party application for monitoring purposes. Investigating a specific metric is easy as each metric can be drilled down into more detail for each cluster node.
Not only are the MQTT metrics useful for monitoring the MQTT deployment, the system metrics of the machines the HiveMQ nodes are running on are equally important. Especially in identifying if a node is running out of disc space or CPU, the Cluster statistics in the Control Center deliver good insights into each machine’s attributes and current workload.
In an average MQTT deployment an MQTT broker sends and receives millions of MQTT messages during a short period of time. Analyzing all this information from the cluster log files is very time-consuming, especially if one is interested in knowing what is going on with a specific MQTT client or topic subscription.
Instead of searching through all the log files, HiveMQ provides an easier approach of doing this. Based on a combination of filters for client IDs and/or topics, the Trace Recordings enables the creation of individual log files in a human readable format that report selected MQTT messages for those filters. This makes it much easier to debug a specific client or topic issue that might span a number of cluster nodes.
The core functionality of each MQTT Broker is the reliable delivery of MQTT messages to its MQTT clients. If messages have to be dropped it doesn’t automatically mean that there is a problem, but it certainly represents an unwanted behavior. There can be several reasons for dropping messages, for instance a client message queue at the broker is full or broker-wide memory for queuing QoS 0 messages is exceeded.
To get better insights, the HiveMQ Control Center offers an in-depth look into the reasons why messages got dropped and who the messages got dropped for. Besides the overview of all reasons it’s possible to identify message-dropping clients and analyze these misbehaving MQTT participants in more detail. The fine grained findings will support you for further debugging purposes.
Client Overview and Details
With millions of connected clients, keeping track of your MQTT clients can really become a challenge. The Client Overview within the Control Center provides a list of all clients known to HiveMQ, and if the clients are connected or have a persistent session at the broker but aren’t connected currently. More detailed information about every client is available via the drill down Client Detail View. The Client Detail View contains all the session information about an individual client.
The Control Center offers administrative actions within the Client Details View to allow for disconnecting a client from the broker or removing a client’s persistent session to give you full control over your MQTT deployment. Moreover the Client Details View enables you to not only see the subscriptions and shared subscriptions a client is subscribed to, but also to add and remove both subscriptions and shared subscriptions to and from the client.
Our HiveMQ Control Center is certainly one of the key features we feel are important for any organization deploying HiveMQ and MQTT into production. Feel free to have a look. Try it out by downloading a Trial Version of HiveMQ or have a look into our very detailed documentation.