* use 'manual eth1' to avoid cloud-init blocking on boot waiting for interfaces
* /etc/network/interfaces originates from a hardcoded file in the image
* cloud-init places /etc/cloud/on-ec2 (or similar) flag file
* on interface add/remove have a rule that fires, checks ec2 flag file, then updates /etc/network/interfaces, and ifup/down
Adding notes from IRC:
* use 'manual eth1' to avoid cloud-init blocking on boot waiting for interfaces interfaces originates from a hardcoded file in the image interfaces, and ifup/down
* /etc/network/
* cloud-init places /etc/cloud/on-ec2 (or similar) flag file
* on interface add/remove have a rule that fires, checks ec2 flag file, then updates /etc/network/