# What's New
This section lists the new features introduced in EMQX 5.0 and 5.1.
# Core + Replica Cluster Architecture
EMQX 5.0 adopts a new Mria cluster architecture. With this architecture, one EMQX cluster can support 100 million concurrent MQTT connections (opens new window), and more, making it the world’s most scalable open-source MQTT broker.
Besides this obvious scalability improvement, the Mria cluster architecture is also capable of reducing the risk of brain-splitting and its effects in large-scale deployments, to empower our clients with more stable and reliable IoT data access services.
To get started, see Create an EMQX Cluster.
# Rolling Upgrades without Downtime
Starting with EMQX Enterprise 5.1.0, the system now supports seamless rolling upgrades for the cluster. This enhances the overall system availability and reliability by allowing transitions to newer versions without any service interruption.
# MQTT over QUIC
EMQX 5.0 introduced QUIC support (MQTT over QUIC) as an experimental feature and designs a unique messaging mechanism and management approach. In EMQX 5.1 we added QUIC multistream (opens new window) support and from now on consider this feature as "generally available".
As the underlying transport protocol of the next-generation Internet protocol HTTP/3, QUIC (opens new window) can provide connectivity for the modern mobile Internet with less connection overhead and message latency compared to TCP/TLS protocols. Therefore, EMQX attempted to replace the transport layer of MQTT with QUIC, which led to the MQTT over QUIC.
To evaluate MQTT over QUIC and verify how it could improve network connectivity, please read Use MQTT over QUIC .
# Backup and Restore
EMQX 5.1 introduces a set of command-line tools for backup and restore, allowing you to export data and configuration files from the built-in database as a compressed package and restore them to a new cluster.
::: details Usage example Create a backup:
$ ./bin/emqx ctl data export ... Data has been successfully exported to data/backup/emqx-export-2023-06-21-14-07-31.592.tar.gz.
Restore a backup:
./bin/emqx ctl data import <File>
Find more details on Backup and Restore page.
# Redesigned IoT Data Integration
Support sending data to WebHook or establishing bidirectional data bridging with external MQTT services.
EMQX visualizes the data integration process with the Flows feature on Dashboard. Now you can easily check how the rules engine processes IoT data and how data flows to external data services or devices.
On different data bridging that EMQX supports and how to configure, see Data Bridges.
# Flexible Authentication/Authorization
EMQX 5.x offers a built-in client authentication/authorization feature, users only need to do some simple configuration work before integrating with various data sources for user authentication and ensuring data security under various scenarios.
- Support using Dashboard for the authentication/authorization configuration on the cluster level;
- Support using Dashboard for configuration, commissioning and management;
- Support adjusting the running order of the authenticators and authorization checkers;
- Achieve complete observability with statistics on execution speed and number of times;
- Support authentication configuration on a listener-level, to provide more flexible access capabilities.
On how to run authentication/authorization configuration with EMQX Dashboard or configuration files, you can continue to read Access Control.
# User-Friendly EMQX Dashboard
In EMQX 5.x, we have redesigned the EMQX Dashboard, enhancing the visual experience and supporting more powerful and user-friendly features.
- New UI/UX design: Great enhancement of real-time observability
- Optimized menu structure: Fast and direct access to contents
- Data monitoring and management: Important data at a glance
- Visualized access control: Out-of-the-box authentication/authorization management
- Visualized data flows: Using Flows users can clearly see how data flows from devices or clients through the rule engine
- Configuration updates during runtime: Hot update that takes effect immediately
# Overload Protection, Limiter and Buffer Queue for Bridges
The new Limiter feature enhances connection and messaging rate control by providing more precise and layered rate control options. It ensures that the system operates under the expected workloads by limiting the client behavior at the client, listener, or node levels. The combination of the Overload protection and Limiter features prevents the clients from becoming overwhelmed or receiving excessive request traffic and ensures stable system operation.
A generic buffer queue is also added for all bridges, allowing buffer messages generated under stressful conditions. This buffer can be configured to store messages in either memory or disk cache when external resources are unavailable, such as during network fluctuations or service downtime. Buffered messages will be sent once the service is restored. However, requests in the buffer may expire, which is a big difference compared to version 4. If the amount of buffered data exceeds the limit, it will be discarded following the First In First Out (FIFO) rule.
# Cloud Native and EMQX Operator
Horizontal expansion and elastic clusters are features that a cloud-native application must support.
EMQX Kubernetes Operator (opens new window) lets you take full advantage of the Replicant node of EMQX 5.x. You can deploy a stateless EMQX node with Kubernetes Deployment and then build the EMQX cluster that supports large-scale MQTT connections and message throughput.
# New Gateway Framework
EMQX 5.1 presents a new extended gateway framework with reconstructed underlying architecture for multi-protocol access and a unified configuration format and management interface:
- Unified statistic and monitoring indicators: EMQX 5.0 provides the gateway/client-level statistic indicators, for example, number of bytes sent and received, messages, etc.
- Independent connection and session management: Different from EMQX 4.x, gateway clients are also managed under the MQTT client list, EMQX 5.0 has created an independent gateway page for each gateway, and one Client ID can be reused across gateways.
- Independent client authentication: Different from EMQX 4.x, where the gateway authentication is also managed under the MQTT client, EMQX 5.0 supports configuring a unique authentication mechanism for each gateway.
- Easy to expand with clear specifications: The framework provides a set of standard concepts and interfaces to make it easier to customize the gateways.
The new gateway framework further improves EMQX's usability by unifying access and managing multiple protocols. Now clients implementing third-party protocols can also leverage the advantages of EMQX, such as data integration, safe and reliable authentication/authorization, billion-level horizontal expansion capabilities, etc.
# More Feature Updates
# Simplified Configuration
emqx.conf configuration file has been changed to a concise and readable HOCON (opens new window) format, and contains commonly used configuration items by default, to improve the readability and maintainability.
# Improved REST API
REST API is now compliant with the OpenAPI 3.0 specification, and comes with clear and rich API documentation.
# Rapid Troubleshooting
More diagnostic tools such as slow subscriptions and online tracing are added so users can quickly troubleshoot issues in production.
# Structured Logs
Machine (indexer) friendly structured logs in JSON format are supported. Error logs are consistently tagged with 'msg' tokens to facilitate locating the cause of the problem.
# Flexible Expansion and Customization
A new plugin architecture is developed, with which users can compile, distribute, and install their extension plugins in the form of independent plugin packages to customize and extend the usage of EMQX.
- Core + Replica Cluster Architecture
- Rolling Upgrades without Downtime
- MQTT over QUIC
- Backup and Restore
- Redesigned IoT Data Integration
- Flexible Authentication/Authorization
- User-Friendly EMQX Dashboard
- Overload Protection, Limiter and Buffer Queue for Bridges
- Cloud Native and EMQX Operator
- New Gateway Framework
- More Feature Updates