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A single TGW Attachment is made per VPC, and the Attachment is made to all utility subnets in the VPC. Importantly, a TGW attachment must be made to one (and only one) utility subnet in each of the AZs used by the VPC.
TGW Attachments are proposed/offered to Cornell AWS accounts by created in collaboration with the Cloud Team from and connect to one of the set of TGWs used by CIT to offer Direct Connect services.
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