This post originally appeared on the Annexe.
Assuming your builders type is qemu, you may have seen this:
Qemu stderr: Could not initialize SDL(No available video device) - exiting
One solution in the Packer json was to disable graphics:
qemuargs: [ "-nographics" ]
Alternatively, start it headless:
"headless": "true"
If you’ve set the following, you’ll be able to VNC remotely instead. When porting back to Xen, change your /etc/ttys so you can use the serial console as well.