When a master-member account hierarchy is present in AWS and uses IAM instance profiles on a MID server running on the master account, Discovery fails to run in the member accounts, even if the AssumeRole functionality is properly configured to allow master-member traversal.
Steps to Reproduce
Set up a master-member hierarchy with AssumeRole relationship in AWS.
Set up a MID Server on an EC2 instance in the master account.
Set up an IAM role with required policies in the master account.
Assign this new role from #3 as the IAM instance profile to the EC2 instance.
Discover the master-member hierarchy from the instance.
Attempt to discover resources within the member accounts.
There is no workaround for this issue. The problem is corrected in New York Patch 1 and future releases.
Related Problem: PRB1351462