Auto Cluster

AutoCluster - it's a cluster configuration type that provides an easy way to establish a cluster. With this type of configuration Coordinator will be chosen automatically by leader election.

info

If you are a beginner, starting with AutoCluster is recommended since it is simpler to set up and fits the majority of load tests.

AutoCluster Config

This is a basic example of AutoCluster configuration for a cluster with two nodes (Coordinator + 1 Agent):

autocluster-config.json

{
    "TestSuite": "my test suite",
    "TestName": "my test",

    "ClusterSettings": {

        "AutoCluster": {
            "ClusterId": "test_cluster",
            "NATSServerURL": "nats://localhost",

            "Coordinator": {
                "TargetScenarios": ["test_scenario"]
            },

            "Agent": {
                "TargetScenarios": ["test_scenario"],
                "AgentsCount": 1
            }
        }

    }    
}

The main settings are:

• ClusterId is the Id of the NBomber Cluster that will be shared between the NBomber nodes(processes). By this id, NBomber node will be able to discover all participants in the cluster.
• NATSServerURL is the URL to the NATS host server. In our example, we will use a localhost since we host the NATS message broker on the local machine using docker-compose. You can find more info about NATS connection string by this link.
• TargetScenarios specifies target scenarios that will be executed in the cluster. You can specify different TargetScenarios for Coordinator and Agents.
• AgentsCount specifies the number of Agents that should join the cluster (by ClusterId) to allow Coordinator to start a load test.

This is example of AutoCluster configuration with a ScenariosSettings:

auto-cluster-config.json

{
    "TestSuite": "my test suite",
    "TestName": "my test",

    "ClusterSettings": {

        "AutoCluster": {
            "ClusterId": "test_cluster",
            "NATSServerURL": "nats://localhost",

            "Coordinator": {
                "TargetScenarios": ["test_scenario"]
            },

            "Agent": {
                "TargetScenarios": ["test_scenario"],
                "AgentsCount": 1
            }
        }

    },
    
    "GlobalSettings": {

        "ScenariosSettings": [
            {
                "ScenarioName": "test_scenario",
                "LoadSimulationsSettings": [{ "Inject": [1, "00:00:01", "00:00:01"] }]
            }
        ],

        "ReportingInterval": "00:00:05"
    }
}

Run Cluster

var scenario = Scenario.Create("test_scenario", async context => { ... });

NBomberRunner
    .RegisterScenarios(scenario)
    .LoadConfig("auto-cluster-config.json")
    .License("YOUR_ENTERPRISE_LICENSE_KEY")
    .Run();

You can find the complete example by this link.

Run via CLI args

MyLoadTest.dll --config="auto-cluster-config.json"

You can also pass other CLI args:

MyLoadTest.dll --config="auto-cluster-config.json" --cluster-agents-count=5 --license=YOUR_LICENSE_KEY

Here, you can find a list of all available CLI arguments.