Abiquo creates a VDC in AWS as a VPC with one private subnet, and one public subnet and a NAT gateway. Abiquo 5.3 enables the user to create more public subnets, which are subnets with a routing table that routes traffic to the internet gateway.
The default public subnet has a routing table that routes all outbound traffic to the internet gateway. The default private subnet has a routing table with all outbound traffic routed to the NAT gateway.
If you create additional private subnets (in any availability zone), Abiquo will create routes for them to use the NAT gateway. Note that if there was an outage of the availability zone that contains the NAT gateway, the connection from other availability zones would be affected.
To create a new public subnet for AWS, create a private network and select the Internet gateway checkbox.
When the platform creates new public subnets (private networks with an internet gateway), it will not create any new NAT gateways. If you delete the original public subnet, Abiquo will also delete the NAT gateway. But it will replace the routes through the NAT gateway in the main route table with routes to the internet gateway.
Remember that VMs with Elastic IPs in the public subnet are directly connected to the internet and you should take the appropriate security precautions accordingly.