vRealize Orchestrator supports both scale-up and scale-out scalability. 

Scale Up

A single vRealize Orchestrator instance allows up to 300 concurrent workflow instances in the running state. Workflow instances that are in the waiting or waiting-event states do not count toward that number. You can design long running workflows in a way that preserves resources by using the wait elements of the workflow palette. A single vRealize Orchestrator instance supports up to 35,000 managed virtual machines in its inventory.

Scale Out

You can scale out vRealize Orchestrator using a clustered environment, multiple independent vRealize Orchestrator instances, or a combination of both.

In a clustered vRealize Orchestrator environment, multiple vRealize Orchestrator instances can be connected to the same (external) database. Configure all vRealize Orchestrator instances in a cluster using the same settings. Using a vRealize Orchestrator cluster allows you to increase the number of concurrent running workflows, but not the number of managed inventory objects. When clustering a vRealize Orchestrator server, choose between these cluster types.

  • An active-active cluster with up to five active nodes. VMware recommends a maximum of three active nodes in this configuration.

  • An active-passive cluster with only one active node, and up to seven standby nodes.

In a clustered vRealize Orchestrator environment you cannot change workflows while other vRealize Orchestrator instances are running. Stop all other vRealize Orchestrator instances before you connect the vRealize Orchestrator client and change or develop a new workflow.

You can scale out a vRealize Orchestrator environment by having multiple independent vRealize Orchestrator instances (each with their own database instance). This option allows you to increase the number of managed inventory objects. You can use the vRealize Orchestrator Multinode plug-in to replicate the vRealize Orchestrator content, and to start and monitor workflow executions.

Table 1. vRealize Orchestrator Active-Passive Design Decision

Decision ID

Design Decision

Design Justification

Design Implication


Configure vRealize Orchestrator in an active-active cluster configuration.

An active-passive cluster is not currently being implemented as a highly available environment is required.

Active-active clusters allow for both vRealize Orchestrator servers to equally balance workflow execution.



vRealize Orchestrator installation is sized for use by vRealize Automation for typical provisioning operations.

vRealize Orchestrator is designed for customer extensibility. Each customer may utilize vRealize Orchestrator to a different degree as needed by their specific environment.

Customers must assess the impact of any customer created workflows on the environment.