Share a placement group
Placement group sharing allows you to influence the placement of interdependent instances that are owned by separate Amazon accounts. You can share a placement group across multiple Amazon accounts or within your organizations. You can launch instances in a shared placement group.
A placement group owner can share a placement group with:
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Specific Amazon accounts inside or outside of its organization
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An organizational unit inside its organization
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Its entire organization
Note
The Amazon account from which you want to share a placement group must have the following permissions in the IAM policy.
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ec2:PutResourcePolicy -
ec2:DeleteResourcePolicy
Topics
Rules and limitations
The following rules and limitations apply when you share a placement group or when a placement group is shared with you.
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To share a placement group, you must own it in your Amazon account. You cannot share a placement group that has been shared with you.
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When you share a partition or spread placement group, the placement group limits do not change. A shared partition placement group supports a maximum of seven partitions per Availability Zone, and a shared spread placement group supports a maximum of seven running instances per Availability Zone.
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To share a placement group with your organization or an organizational unit in your organization, you must enable sharing with Amazon Organizations. For more information, see Sharing your Amazon resources.
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You are responsible for managing the instances owned by you in a shared placement group.
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You cannot view or modify instances and capacity reservations that are associated with a shared placement group but not owned by you.
Share across Availability Zones
To ensure that resources are distributed across the Availability Zones for a
Region, we independently map Availability Zones to names for each account. This
could lead to Availability Zone naming differences across accounts. For example, the
Availability Zone us-east-1a for your Amazon account might not have the
same location as us-east-1a for another Amazon account.
To identify the location of your Dedicated Hosts relative to your accounts, you
must use the Availability Zone ID (AZ ID). The Availability
Zone ID is a unique and consistent identifier for an Availability Zone across all
Amazon accounts. For example, use1-az1 is an Availability Zone ID for
the us-east-1 Region and it is the same location in every Amazon
account.
To view the Availability Zone IDs for the Availability Zones in your account
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Open the Amazon RAM console at https://console.amazonaws.cn/ram
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The Availability Zone IDs for the current Region are displayed under Your AZ ID in the right panel.
Share a placement group
To share a placement group, you must add it to a resource share. A resource share is an Amazon RAM resource that lets you share your resources across Amazon accounts. A resource share specifies the resources to share, and the consumers with whom they are shared.
If you are part of an organization in Amazon Organizations sharing within your organization is enabled, consumers in your organization are granted access to the shared placement group.
If the placement group is shared with an Amazon account outside of your organization, the Amazon account owner will receive an invitation to join the resource share. They can access the shared placement group after accepting the invitation.
You can share a placement group across Amazon accounts using https://console.amazonaws.cn/ram
Identify a shared placement group
The Amazon Resource Name (ARN) of a placement group contains the 12-digit account ID of the account that owns the placement group. You can use the account ID to identify the owner of a placement group that is shared with you.
You can find the placement group ARN using one of the following methods. For more information, see View placement group information.
Launch an instance in a shared placement group
Important
When using the Amazon CLI to launch an instance in a shared placement group, you
must specify the placement group ID by using the GroupId
parameter.
You can use the placement group name only if you're the owner of the placement group being shared. We recommend using the placement group ID to avoid potential placement group name collisions between Amazon accounts.
You can find the ID of a placement group in the Amazon EC2 console on the
Placement Groups screen or by using the describe-placement-groups
Tip
Use VPC peering to connect instances owned by separate Amazon accounts and get the full latency benefits offered by shared cluster placement groups. For more information, see What is VPC peering?
Unshare a shared placement group
The placement group owner can unshare a shared placement group at any time.
When you unshare a shared placement group, the following changes will take effect.
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The Amazon accounts with which a placement group was shared will no longer be able to launch instances or reserve capacity.
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If your instances were running in a shared placement group, they will be disassociated from the placement group but continue to run normally in your Amazon account.
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If you had capacity reservations in a shared placement group, they will be disassociated from the placement group but you will continue to have access to them in your Amazon account.
You can unshare a shared placement group using one of the following methods.