VPC Peering

Configuration

• Have to add routes to both two subnets' route table.

• No unidirection access if only one route is added to one subnet's route table.

OR

No traffic allowed from A -> B and B -> A.

Steps to create VPC peering

1. Create VPC peering requests(in account A)
2. Accept VPC peering requests(in account B)
3. Update/Create route tables to transmit all requests to the peered CIDR to peered VPC(in account A)
4. Update/Create route tables to transmit all requests to the peered CIDR to peered VPC(in account B)
5. (Optional) Allow DNS resolving(in account A and B)
6. (Optional) Associate Private Hosted Zone following the steps below(in account A and B)
7. Update security groups (Can use OTHER_AWS_ACCOUNT/SG_ID in the inbound/outbound rule to allow traffic from security group in other aws accounts)

VPC Peering with Private Hosted Zone

This process has to be done using command line.

# The AWS account that created the private hosted zone must first submit a CreateVPCAssociationAuthorization request

aws route53 create-vpc-association-authorization --hosted-zone-id HOSTED_ZONE_ID --vpc VPCRegion=us-west-2,VPCId=VPC_ID_IN_OTHER_ACCOUNT

# Then the account that created the VPC must submit an AssociateVPCWithHostedZone request.
aws route53 associate-vpc-with-hosted-zone --hosted-zone-id SAME_HOSTED_ZONE_ID --vpc VPCRegion=us-west-2,VPCId=SAME_VPC_ID