Troubleshooting Auto Scaling

To retrieve an error message from the description of Auto Scaling activities, use the as-describe-scaling-activities command. Alternatively, you can use the DescribeScalingActivities API action. For more information about the API action, go to DescribeScalingActivities in the Auto Scaling API Reference.

The as-describe-scaling-activities command takes the following arguments:

as-describe-scaling-activities [ActivityIds [ ActivityIds...] ] [--auto-scaling-group value][--max-records value][General Options]

In this example, you'll get the xml description of the Auto Scaling activities for the MyASGroup Auto Scaling group.

PROMPT>as-describe-scaling-activities  --auto-scaling-group MyASGroup --show-xml

Auto Scaling returns the following:

<DescribeScalingActivitiesResponse xmlns="http://ec2.amazonaws.com/doc/2011-01-01/">
<DescribeScalingActivitiesResult>
<Activities>
   <member>
     <StatusCode>Failed</StatusCode>
     <Progress>0</Progress>
     <ActivityId>063308ae-aa22-4a9b-94f4-9fae70b82ad0</ActivityId>
     <StartTime>2012-04-12T17:32:07.882Z</StartTime>
     <AutoScalingGroupName>MyASGroup</AutoScalingGroupName>
     <Cause>At 2012-04-12T17:31:30Z a user request created an AutoScalingGroup changing the desired capacity from 0 to 1.  At 2012-04-12T17:32:07Z an instance was started in response to a difference between desired and actual capacity, increasing the capacity from 0 to 1.</Cause>
     <Details>{}</Details>
     <Description>Launching a new EC2 instance.  Status Reason: The image id 'ami-4edb0327' does not exist. Launching EC2 instance failed.</Description>
     <EndTime>2012-04-12T17:32:08Z</EndTime>
     <StatusMessage>The image id 'ami-4edb0327' does not exist. Launching EC2 instance failed.</StatusMessage>
   </member>
</Activities>
  </DescribeScalingActivitiesResult>
  <ResponseMetadata>
   <RequestId>7a641adc-84c5-11e1-a8a5-217eb05262e2</RequestId>
  </ResponseMetadata>
</DescribeScalingActivitiesResponse>
 

The response includes a list of Activities associated with the MyASGroup Auto Scaling group. The StatusCode contains the current status of the activity. The StatusMessage contains the error message, which is the verbose description of the activity status.

Troubleshooting Auto Scaling issues involves looking at how your Amazon EC2 AMIs and instances are configured. You can create, access, and manage your AMIs and instances using one of the Amazon EC2 interfaces: the AWS Management Console, the command line interface (CLI), or the Query API. You will have to install the Amazon EC2 command line tools before you can use them. For more information go to Getting Started with the Command Line Tools in the Amazon Elastic Compute Cloud User Guide. For information on using the Query API, go to Making API Requests in the Amazon Elastic Compute Cloud User Guide.

The following tables list the types of error messages and provide links to the troubleshooting resources that you can use as you work with your Auto Scaling issues.