Block public access for Amazon EBS snapshots

• Block all sharing — Blocks all public sharing of your snapshots. Users in the account can't request new public sharing. Additionally, snapshots that were already publicly shared are treated as private and are no longer publicly available.

• Block new sharing — Blocks only new public sharing of your snapshots. Users in the account can't request new public sharing. However, snapshots that were already publicly shared, remain publicly available.

Considerations

Keep the following in mind when working with block public access for snapshots.

• Block public access for snapshots does not prevent private snapshot sharing.

• Enabling block public access for snapshots in block all sharing mode does not change the permissions for snapshots that are already publicly shared. Instead, it prevents these snapshots from be publicly visible and publicly accessible. Therefore, the attributes for these snapshots still indicate that they are publicly shared, even though they are not publicly available.

  If you later disable block public access or change the mode to block new sharing, these snapshots will become publicly available again.

• Block public access for snapshots is a Regional setting. It applies to all snapshots in the Region in which it is enabled. You need to enable block public access for snapshots in each Region in which you want to prevent the public sharing of your snapshots.

• Block public access is an account-level setting. It applies to all users, including administrator users, in the account. You can't enable block public access for snapshots at the organization level.

• Block public access for snapshots does not prevent the public sharing of EBS-backed AMIs. If you enable block public access for snapshots, users can still publicly share EBS-backed AMIs. If an EBS-backed AMI is publicly shared, users with access to that AMI can create volumes from its associated snapshots. To prevent public sharing of your AMIs, enable block public access for AMIs.

• Block public access for snapshots is not supported with local snapshots on AWS Outposts.