The VyOS build system has targets for cloud environments, but ships with a broken cloud-init. In EC2, instance never come up as accessible to the user, showing eth0 as down in the cloud-init boot messages on ttyS0 and an inability to make network connection with the 169.254.169.254 address.
I have brought this issue up in slack and been told to use separate AMI build repos to achieve this goal. The problem isnt the image being built, its how cloud-init interacts with the network stack of VyOS. An AWS instance does briefly get an IP - if i start a ping run against its IP while its initializing i get a single echo reply out of 100s of pings sent and then it goes dark again.
Clouds are a pretty major target for the OS and likely a major revenue source. Could VyOS build system please address the issue? Its likely going to require changes to cloud-init to deal with how VyOS configures its networks, but a config.boot.default explicitly specifying dhcp for eth0 doesnt help - cloud-init appears to override the address assignment from the vyatta tier at the linux tier and then everything breaks. Obviously once that happens you're screwed in AWS because those "people" dont provide a proper console like every other sane cloud on the planet.