Create a placement group for your EC2 instances

You can use a placement group to control the placement of instances relative to each other. After you create a placement group, you can launch instances in the placement group.

Limitation

You can create a maximum of 500 placement groups per Region.

Console

To create a placement group

1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

2. In the navigation pane, choose Placement Groups.

3. Choose Create placement group.

4. Specify a name for the group.

5. Choose the placement strategy for the group: Cluster, Spread, or Partition.

   If you chose Spread, you must choose the spread level: Rack or Host.

   If you chose Partition, you must enter the number of partitions for the group.

6. (Optional) To add a tag, choose Add new tag, and then enter a key and value.

7. Choose Create group.

AWS CLI

Use the create-placement-group command.

To create a cluster placement group

The following example creates a placement group that uses the cluster placement strategy, and it applies a tag with a key of purpose and a value of production.

aws ec2 create-placement-group \
    --group-name my-cluster \
    --strategy cluster \
    --tag-specifications 'ResourceType=placement-group,Tags={Key=purpose,Value=production}'

To create a partition placement group

The following example creates a placement group that uses the partition placement strategy, and specifies the five partitions using the --partition-count parameter.

aws ec2 create-placement-group \
    --group-name HDFS-Group-A \
    --strategy partition \
    --partition-count 5

PowerShell

To create a placement group

The following New-EC2PlacementGroup command creates a cluster placement group.

New-EC2PlacementGroup -GroupName my-placement-group -Strategy cluster