Manage cloud alarms

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. 

If you would like the platform to notify you when an alarm activates, create an Alert for it in Control view.

• Alerts are a group of one or more alarms. They are like a worker monitoring a group of alarms; when all the lights for the group are lit up, then the worker takes action and activates the alert. Alerts can also trigger action plans to perform automated actions when their alarms activate. After you create an alert, create an action plan in Control view with the alert as a trigger.

You can create alarms for built-in VM metrics or scaling group metrics, as well as custom metrics created using the API for VMs, scaling groups, virtual appliances, and virtual datacenters. 

• You cannot create alarms for cloned VMs that are part of a scaling group. This is because scaling groups have aggregate alarms that are associated with the base VM. 

To display alarms in virtual datacenters:

1. Go to Virtual datacenters 
2. Select a virtual datacenter or All virtual datacenters
3. Go to Alarms

Before you begin:

1. Configure the metrics you will use in the alarm. See VM monitoring and metrics and Custom Metrics Resources.

To create an alarm:

1. Go to Virtual datacenter → Alarms
2. Select virtual datacenter, virtual appliance, scaling group, or VM
3. Click the + add button
4. Enter the alarm details
   
   
   
   For more details see GUI Create alarm
   
   
5. Click Save

The platform will create the alarm for the metric. If you would like the platform to notify you when an alarm is triggered, create an Alert.

For API documentation about alarms on an entity, see the API documentation for the entity's resource. For example, for VMs, see VirtualMachinesResource.

When you edit an alarm, you cannot modify the metric or the entity.

When you edit an alarm, there is an extra field, "Active", that shows if the alarm is activated or not.

After you save the alarm, the platform will start to evaluate it again with new data when it receives the next set of metrics datapoints.

You can delete any alarm at any time, even if it is part of one or more alerts. The platform will not warn you that the alarm is used in an alert. However, you can check this in Control view. After you delete an alarm, you cannot recover it.

You can also remove an alarm from an alert.

To delete an alarm:

1. Go to Virtual datacenters or Infrastructure →  Alarms
2. Select the alarm and delete it by clicking on the trash bin delete button

To remove an alarm from an alert:

1. Go to Control → Alerts → edit alert

2. Select the alarm, click the trash bin delete button, and confirm
   The platform will remove it from this alert, but it will remain in all other alerts that it is associated with