'qm terminal' looses connection to console (or something)

Jan 12, 2015
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I am booting my Linux virtual from and ISO image and adding the "...console=tty0 console=ttyS0" manually from the boot menu. I can run `qm terminal <VMID>` from the command line on the proxmox server and display all the boot output as the VM is booting. Very nice.

I'm not, however, able to get a login prompt. The qm terminal only produces output up to:

* Starting User-mode networking switch uml_switch [ OK ]
* Starting MD monitoring service mdadm --monitor [ OK ]
* Restoring resolver state... [ OK ]
* Stopping System V runlevel compatibility [ OK ]​

On the VM, if I login from the VNC console, I do not see a getty running on tty0. Only tty4 - tty6. Is this the issue?
 
I think it's something to do with my Ubuntu ISO. I had to add "serialtty=ttyS0" in addition to the aforementioned boot args. Found it in the ramdisk image used for the ISO (scripts/casper-bottom/22serialtty)