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4) Review Permissions Policies
To view the underlying Permissions Policies that are required in your custom IAM Role, click on the link name of the selected IAM Role on the EC2 Instance summary page.
To display the Permissions Policies, select the The IAM Role , and the IAM Role Edit page will be shown with the Permissions Policies listed.
Note: The following policies listed are required in order for SSM to function properly.
AmazonSSMManagedInstanceCore
CloudWatchAgentServerPolicy
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