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E-MapReduce:View scaling records (Hadoop clusters only)

Last Updated:Mar 25, 2026

The Scaling Records tab shows the outcome of each scaling activity on your Hadoop cluster. Use this page to answer questions like: Did the scale-out complete? Why was a scaling rule rejected? Is an activity still running?

Prerequisites

Before you begin, ensure that you have:

  • A Hadoop cluster with auto scaling configured

View scaling records

  1. Log on to the EMR on ECS console.

  2. In the top menu bar, select a region and resource group.

  3. On the EMR on ECS page, click the name of the target cluster.

  4. Click the Auto Scaling tab.

  5. Click the Scaling Records tab. Each record shows the status of a scaling activity. The following table describes the possible statuses.

    Status

    Description

    Successful

    Nodes are added to or removed from the cluster based on the scaling rule.

    Note

    During a scale-out for a Hadoop cluster, abnormal ECS nodes are automatically released. Only healthy nodes are kept for subsequent computing.

    Datalake clusters now support custom best-effort delivery and provide a comprehensive alert mechanism. Select a scale-out delivery mechanism as needed. Upgrade as soon as possible.

    Failed

    No nodes are added to or removed from the cluster based on the scaling rule.

    Running

    The scaling activity is in progress.

    Request Denied

    The scaling rule was rejected for one of the following reasons: (1) the rule execution would cause the number of instances to exceed the maximum limit or fall below the minimum limit, or (2) the rule was triggered while a previous scaling activity was still in progress.