Itential Automation Gateway (IAG) supports multiple architecture and deployment models designed to meet different scalability, availability, and infrastructure requirements. Understanding these models will help you select the optimal deployment strategy for your environment.
Gateway servers (also called controller nodes or core servers) manage automation resources, handle incoming requests from gateway clients, and maintain connections to Gateway Manager. These nodes serve as the control plane for your IAG deployment and are responsible for orchestrating service execution across the cluster. In “all-in-one” deployments, gateway servers also execute services directly on the same node.
Runner nodes (also called runners) are specialized execution-only nodes that run automation services such as scripts, playbooks, and plans on behalf of the gateway server, which handles coordination and management. In all-in-one deployments, the gateway server performs both roles on its own. As your workloads increase, you can add runner nodes to distribute execution and process more tasks in parallel. Each runner node you add increases the cluster’s overall capacity. To add one, place the IAG 5 binary on a server and point it at the cluster. For detailed procedures, see Configure distributed execution clusters.
In high availability configurations, only one gateway server can be active at a time. The active node maintains the connection to Gateway Manager and handles all incoming requests. Standby nodes remain in a “hot standby” state, ready to take over immediately if the active node fails. For more information, see Configure high availability clusters.
A gateway cluster consists of one or more gateway servers and runner nodes that share the same automation resources (services, repositories, configuration, etc.) and appear as a single, unified execution environment to Itential Platform. When Itential Platform connects to IAG 5 through Gateway Manager, it connects to the cluster, not individual servers. You can deploy a single cluster or multiple independent clusters to separate environments by geography or network segment. All nodes in a cluster communicate through a shared database (etcd or Amazon DynamoDB) for resource sharing and coordination.
The most basic IAG deployment consists of a single gateway server that handles both management and execution functions on the same node. In this “all-in-one” configuration, services run directly on the gateway server without any separate runner nodes.
This deployment model provides basic high availability with one active gateway server and one or more standby gateway servers. All nodes operate in “all-in-one” mode, performing both management and execution functions on the same node without separate runner nodes.
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This architecture separates management functions from execution by introducing dedicated runner nodes. One or more gateway servers handle management and coordination, while multiple runner nodes handle service execution.
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This model combines high availability gateway servers with distributed runner nodes, providing both resilience and scalability.
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For complex environments, you can deploy multiple independent clusters, each with its own cluster ID and potentially its own shared database.
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When you deploy multiple clusters, you designate one as the Platform default cluster in Admin Essentials. Gateway-dependent features use the default cluster unless a feature-specific cluster is configured. For more information, see Gateway configuration.
When selecting an architecture model, consider these factors in order of priority:
The IAG architecture is designed to allow evolution from simpler to more complex models as your requirements grow, enabling you to start with a basic deployment and scale up as needed.