Rackspace Auto Scale Control Panel User Guide - Create a Scaling Policy

The Create a scaling group article describes how to set the parameters for scaling policies through the scaling group configuration. This section discusses the Auto Scale current policy options and how group configurations affect policy execution. A scaling policy determines what actions the scaling group take and when they are taken. You can create scaling policies for an existing scaling
group at any time by returning to the group configuration page. Typically, you will create at least two policies: one to scale up and one to scale down. You can create up to 1000 policies per group.

There are two steps to create a scaling policy:

Create a scaling policy

  1. On the Create Scaling Group page, click Create Policy.
  2. Enter information for the following values:
    • Name: Specify a name for the policy, for example, Scale up by 10 on
      Fridays at 5p.m.
    • Scale Trigger: Select how the policy will be triggered, either by a
      specific schedule or a webhook. Fill in the schedule or webhook
      information according to your selection:
      • Scheduled (repeating): Specify how often the policy will occur and
        when.
      • Scheduled (once): For one occurrence.
      • Scheduled (cron): Enter a cron expression. You can click Cron
        Expression Helper
        then copy the expression into Auto Scale.
      • Webhook URL: You must create and configure the webhook by using
        the Auto Scale API. To learn more about this, read about
        Webhooks
        in the Auto Scale API Developer's Guide.
    • Amount: Select Scale Up or Scale Down, enter an integer, and
      select Servers or Percent. If you specify Scale Up by 2
      Servers
      , the policy will add two servers to your scaling group when
      the policy is triggered. If you specify Scale Up by 2 Percent, the
      policy will add servers to equal the equivalent of two percent of your
      current scaling group, whatever size it is. See Scale Up by Percentage
      Policy

      for a visual explanation.
    • Cooldown Period: The policy cooldown, prevents a policy from being
      executed too frequently. For schedule-based policies, we advise leaving
      this value empty or setting it to 0 (zero). This option is available for
      Scheduled (cron) and Webhook URL triggers only.
  3. Click Create Policy. The dialog box closes and the scaling policy that you created is
    added to the list of scaling policies on the page.

Test your configuration

After the scaling group and scaling policy are created, configuration can be
tested by changing the minimum number of entities for the group and watching the
new server or servers being added.

Next steps

After you have created a scaling group and policy, following are some next steps
that you might take:

User Guide sections