Amazon Elastic MapReduce
API Reference (API Version 2009-03-31)
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RunJobFlow

Description

RunJobFlow creates and starts running a new job flow. The job flow will run the steps specified. Once the job flow completes, the cluster is stopped and the HDFS partition is lost. To prevent loss of data, configure the last step of the job flow to store results in Amazon S3. If the JobFlowInstancesConfig KeepJobFlowAliveWhenNoSteps parameter is set to TRUE, the job flow will transition to the WAITING state rather than shutting down once the steps have completed.

For additional protection, you can set the JobFlowInstancesConfig TerminationProtected parameter to TRUE to lock the job flow and prevent it from being terminated by API call, user intervention, or in the event of a job flow error.

A maximum of 256 steps are allowed in each job flow.

If your job flow is long-running (such as a Hive data warehouse) or complex, you may require more than 256 steps to process your data. You can bypass the 256-step limitation in various ways, including using the SSH shell to connect to the master node and submitting queries directly to the software running on the master node, such as Hive and Hadoop. For more information on how to do this, go to Add More than 256 Steps to a Job Flow in the Amazon Elastic MapReduce Developer's Guide.

For long running job flows, we recommend that you periodically store your results.

Request Parameters

For information about the common parameters that all actions use, see Common Parameters.

AdditionalInfo

A JSON string for selecting additional features.

Type: String

Length constraints: Minimum length of 0. Maximum length of 10280.

Required: No

AmiVersion

The version of the Amazon Machine Image (AMI) to use when launching Amazon EC2 instances in the job flow. The following values are valid:

  • "latest" (uses the latest AMI)
  • The version number of the AMI to use, for example, "2.0"

If the AMI supports multiple versions of Hadoop (for example, AMI 1.0 supports both Hadoop 0.18 and 0.20) you can use the JobFlowInstancesConfig HadoopVersion parameter to modify the version of Hadoop from the defaults shown above.

For details about the AMI versions currently supported by Amazon Elastic MapReduce, go to AMI Versions Supported in Elastic MapReduce in the Amazon Elastic MapReduce Developer's Guide.

Type: String

Length constraints: Minimum length of 0. Maximum length of 256.

Required: No

BootstrapActions.member.N

A list of bootstrap actions that will be run before Hadoop is started on the cluster nodes.

Type: BootstrapActionConfig list

Required: No

Instances

A specification of the number and type of Amazon EC2 instances on which to run the job flow.

Type: JobFlowInstancesConfig

Required: Yes

JobFlowRole

An IAM role for the job flow. The EC2 instances of the job flow assume this role. The default role is EMRJobflowDefault. In order to use the default role, you must have already created it using the CLI.

Type: String

Length constraints: Minimum length of 0. Maximum length of 10280.

Required: No

LogUri

The location in Amazon S3 to write the log files of the job flow. If a value is not provided, logs are not created.

Type: String

Length constraints: Minimum length of 0. Maximum length of 10280.

Required: No

Name

The name of the job flow.

Type: String

Length constraints: Minimum length of 0. Maximum length of 256.

Required: Yes

NewSupportedProducts.member.N

A list of strings that indicates third-party software to use with the job flow that accepts a user argument list. EMR accepts and forwards the argument list to the corresponding installation script as bootstrap action arguments. For more information, see Launch a Job Flow on the MapR Distribution for Hadoop. Currently supported values are:

  • "mapr-m3" - launch the job flow using MapR M3 Edition.
  • "mapr-m5" - launch the job flow using MapR M5 Edition.
  • "mapr" with the user arguments specifying "--edition,m3" or "--edition,m5" - launch the job flow using MapR M3 or M5 Edition respectively.

Type: SupportedProductConfig list

Required: No

ServiceRole

The IAM role that will be assumed by the Amazon EMR service to access AWS resources on your behalf.

Type: String

Length constraints: Minimum length of 0. Maximum length of 10280.

Required: No

Steps.member.N

A list of steps to be executed by the job flow.

Type: StepConfig list

Required: No

SupportedProducts.member.N

A list of strings that indicates third-party software to use with the job flow. For more information, go to Use Third Party Applications with Amazon EMR. Currently supported values are:

  • "mapr-m3" - launch the job flow using MapR M3 Edition.
  • "mapr-m5" - launch the job flow using MapR M5 Edition.

Type: String list

Length constraints: Minimum length of 0. Maximum length of 256.

Required: No

Tags.member.N

A list of tags to associate with a cluster and propagate to Amazon EC2 instances.

Type: Tag list

Required: No

VisibleToAllUsers

Whether the job flow is visible to all IAM users of the AWS account associated with the job flow. If this value is set to true, all IAM users of that AWS account can view and (if they have the proper policy permissions set) manage the job flow. If it is set to false, only the IAM user that created the job flow can view and manage it.

Type: Boolean

Required: No

Response Elements

The following element is returned in a structure named RunJobFlowResult.

JobFlowId

An unique identifier for the job flow.

Type: String

Errors

For information about the errors that are common to all actions, see Common Errors.

InternalServerError

Indicates that an error occurred while processing the request and that the request was not completed.

HTTP Status Code: 500

Examples

Sample Request

POST / HTTP/1.1
Content-Type: application/x-amz-json-1.1
X-Amz-Target: ElasticMapReduce.RunJobFlow
Content-Length: 734
User-Agent: aws-sdk-ruby/1.9.2 ruby/1.9.3 i386-mingw32
Host: us-east-1.elasticmapreduce.amazonaws.com
X-Amz-Date: 20130715T210803Z
X-Amz-Content-Sha256: 8676d21986e4628a89fb1232a1344063778d4ffc23d10be02b437e0d53a24db3
Authorization: AWS4-HMAC-SHA256 Credential=AKIAIOSFODNN7EXAMPLE/20130715/us-east-1/elasticmapreduce/aws4_request, SignedHeaders=content-length;content-type;host;user-agent;x-amz-content-sha256;x-amz-date;x-amz-target, Signature=71f79725c4dbe77c0e842718485f0b37fe6df69e1153c80f7748ebd9617ca2f3
Accept: */*


{
    "Name": "Development Job Flow",
    "Instances": {
        "KeepJobFlowAliveWhenNoSteps": "false",
        "TerminationProtected": "false",
        "InstanceGroups": [{
            "Name": "Master Instance Group",
            "InstanceRole": "MASTER",
            "InstanceCount": 1,
            "InstanceType": "m1.small",
            "Market": "ON_DEMAND"
        }]
    },
    "Steps": [{
        "Name": "Example Streaming Step",
        "ActionOnFailure": "CANCEL_AND_WAIT",
        "HadoopJarStep": {
            "Jar": "/home/hadoop/contrib/streaming/hadoop-streaming.jar",
            "Args": [
                "-input",
                "s3://elasticmapreduce/samples/wordcount/input",
                "-output",
                "s3://examples-bucket/example-output",
                "-mapper",
                "s3://elasticmapreduce/samples/wordcount/wordSplitter.py",
                "-reducer",
                "aggregate"
            ]
        }
    }],
    "BootstrapActions": [],
    "VisibleToAllUsers": "false",
    "NewSupportedProducts": [],
    "AmiVersion": "latest"
}

Sample Response

HTTP/1.1 200 OK
x-amzn-RequestId: a4406d6b-ed92-11e2-9787-192218ecb460
Content-Type: application/x-amz-json-1.1
Content-Length: 31
Date: Mon, 15 Jul 2013 21:08:05 GMT

{"JobFlowId": "j-ZKIY4CKQRX72"}