|Metric||A built-in metric that is provided by a hypervisor or provider (e.g. CPU usage) or a custom metric that the user creates and populates using API calls|
|Alarm||An alarm activates when a metric passes a certain threshold. |
If you imagine a dashboard for your metrics, alarms are like red lights that light up when conditions change, for example, when there is a problem.
See Manage cloud alarms and Infrastructure Alarms
|Alert||An alert enables you to configure notifications or actions from alarms. |
Alerts are like a worker monitoring a group of alarms; when all the lights for the group are lit up, the alert is activated.
Alerts can trigger action plans.
|Action plan||A sequence of actions to perform on entities on the platform, such as VMs or scaling groups. An action plan is run by a trigger.|
|Trigger||A trigger is an alert or a schedule that will run the action plan, for example, during times of increased demand.|
|Scaling group||For horizontal autoscaling, create a scaling group for a VM with rules to define how the platform should scale it out. |
You can then include scaling operations in an action plan.
|Vertical scaling||Vertical scaling means scaling up, adding more resources to an existing VM, for example, boosting your CPU and or RAM capacity.|
|Horizontal scaling||Horizontal scaling means scaling out, deploying more VMs when you need more resources.|