The following features are available on all Edge Gateways, license or unlicensed.
OPC UA Module and Drivers
Edge can create OPC UA client connections. The internal OPC UA server in the Edge Gateway acts only as a client and not as a server. This means Edge can connect to other outside OPC servers as a client to fetch data, but can not act as an OPC UA server for outside programs to connect to. Adding the IIoT plugin extends this functionality.
One Week of Internal Storage
An Edge installation can store certain historical data inside Ignition.
Tag History - Up to one week or 10 million data points of history can be stored locally. Pruning will automatically happen, and the historian is automatically enabled and not configurable. An Edge Gateway can only have one realtime Tag provider and one Edge historian. You can learn more about Tag history here.
Alarm Journal - The alarm journal will store all alarm events locally for one week of events. There are limited configuration options; the Alarm Journal can be accessed via the Edge Alarm Journal profile. The Edge alarm journal and audit log can sync under EAM.
Audit Logs - Like the Alarms, the Audit log is limited to one week of local storage. It cannot be configured.
By default, Edge Gateways can have two device connections. Once two devices have been configured, the “add device” UI on the Gateway’s Devices config page will be hidden.
Edge installations have just one project. This project is created automatically if it did not exist, and it cannot be removed. The default project name is "Edge", however as of version 8.0.8, the Edge project can be renamed. For more information, see Edge Gateway Config section.
Two Edge Gateways can be set up with redundancy. An Edge Gateway can only failover to another Edge Gateway (not a standard Ignition Gateway).
Plugins extend Edge's capabilities, each adding a unique set of features. There are five Ignition Edge plugins available: Panel, IIoT, Compute, Sync Services, and EAM. Plugins can be mixed and matched to create the system you need. Please note that a license is required to activate each of the Ignition Edge Plugins. Each Edge plugin offers specific functionality that works best in certain scenarios, but because any combination of plugins can be installed, an Edge Gateway may fill multiple roles and help bridge different architectures.
Ignition Edge Panel creates a standalone HMI at the edge of network. HMIs run in either a web browser or a dedicated application. Either Vision of Perspective may be selected. The Web Browser module is included with Vision.
Ignition Edge IIoT turns any device into an Edge Gateway that publishes data to an MQTT broker. (IIoT was formerly Edge MQTT.) The plugin allows access to the MQTT Transmission, Opto22 SNAP PAC driver, and the Emerson ROC driver modules (manual installation required). In addition, Ignition Edge IIoT exposes Edge’s OPC UA server to external OPC UA clients.
Ignition Edge Compute enables you to remotely run scripts and create REST APIs for interfacing with third-party applications. The plugin allows access to Python scripting, Gateway Event Scripts, and the Web Dev module. The Compute Plugin is new for release 8.0.10.
Ignition Edge Sync Services synchronizes data from the edge of the network to a central Ignition server. The plugin allows access to Sync Services, remote Tags and alarm pipelines, Tag history sync, alarm history sync, and audit log sync.
Ignition Edge EAM brings diagnostics, automatic backup and recovery, central licensing, and project synchronization to your edge-of-network device. The EAM plugin allows this Edge Gateway to be an Agent in an EAM architecture.
All Edge installations are a limited version of the Ignition platform for a significantly reduced cost. This helps keep things simple, and these installations always work with other full versions of Ignition if you need additional functionality. In an Edge installation there are a lot of visual changes to the Gateway Webpage, and some pages have been removed to avoid confusion. You can see below that after installing Edge, the traditional orange Ignition logos are replaced with new green Edge logos so a Gateway can be easily identified. For more information, see Edge Gateway.
Ignition Edge Compared with Ignition
Because Edge is a lean solution, it does have some functionality limitations compared to full Ignition. Ignition and Ignition Edge share the same basic platform, but Edge is a leaner version of Ignition made specifically for use in on edge-of-network devices. Ignition comes with unlimited Tags, Clients, and database connections, while Ignition Edge comes with unlimited Tags, two Clients (one local and one remote) and no database connectivity.
Database access is disabled. This means that any database queries or bindings will not work, and the user sources that require a database connection will not be available. The Status and Configure pages of the Gateway Webpage have been updated to remove these features and reduce confusion. Despite this restriction, some "historical" storage can happen inside of Ignition.
All Gateway level scripting is disabled including Gateway Event Scripts and Tag Event scripts. This does not affect project or client scoped scripts. If you wanted to take advantage of Gateway Events Scripts and Tag Events Scripts with an Edge installation, you can do so through the use of the Compute Plugin. Keep in mind that you will not see the “Gateway Events” menu item in the Designer on unlicensed Gateways. Applying a compute license will require a Designer restart before the menu item will appear.
Gateway and Project Backups
A Gateway backup made in an Edge installation will work perfectly in other Edge installations. Edge Gateway Backups are not compatible with Ignition Gateways, so you may not take an Edge Gateway Backup and restore it on an Ignition Gateway. Nor may you take an Ignition Gateway Backup and restore it on an Edge Gateway.
However, you can still export Tags, windows, and other project resources in the Designer from full Ignition Gateways, and import them into an Edge project, or vice versa.
Edge's core functionality and plugins largely determine which modules run on the platform. Third-party modules will not run on an Edge Gateway, with the exception any third-party module explicitly stated by a plugin, such as the Edge IIoT Plugin.