Configure autoscaling
Autoscaling allows you to adjust cluster capacity based on Ambari metrics and alerts, as well as schedule time-based capacity adjustment. Refer to this section if you would like to configure autoscaling for Cloudbreak-managed clusters.
When creating an autoscaling policy, you define:
- An alert that triggers a scaling policy. An alert can be based on an Ambari metric or can be time-based.
- A scaling policy that adds or removes a set number of nodes to a selected host group when the conditions defined in the attached alert are met.
Metric-based autoscaling
Cloudbreak accesses all available Ambari metrics and allows you to define alerts based on these metrics. For example:
| Alert Definition | Policy Definition |
|---|---|
| ResourceManager CPU alert with CRITICAL status for 5 minutes | Add 10 worker nodes |
| HDFS Capacity Utilization alert with WARN status for 20 minutes | Set the number of worker nodes to 50 |
| Ambari Server Alerts alert with CRITICAL status for 15 minutes | Decrease the number of worker nodes by 80% |
Time-based autoscaling
Time-based alerts can be defined by providing a cron expression. For example:
| Alert Definition | Policy Definition |
|---|---|
| Every day at 07:00 AM (GMT-8) | Add 90 worker nodes |
| Every day at 08:00 PM (GMT-8) | Remove 90 worker nodes |
 | Note |
|---|---|
Cluster resizing is not supported for HDF clusters. |
Overview of configuring autoscaling
- Enable autoscaling.
- Define a time-based or metric-based alert.
- Create a scaling policy.
- Review and, if needed, configure autoscaling settings.