how to enable VT100 text console for guest (fedora-34)

tolland

I have a fedora-34 guest which I am having trouble booting because if a kernel issue. For the purpose of debugging I would like to get a text mode VT100 console on the machine.

I've followed the instructions here:
https://discussions.citrix.com/topic/391538-how-to-get-text-console-from-xe-console-command-on-xenserver71/page/2/

however the vm is still displaying RFB as the protocol version in the console-list:

uuid ( RO)             : 9cafacae-afed-5d2f-8614-4440a2b03ef6
          vm-uuid ( RO): 2909abd6-3bf1-9bde-21d7-d6fcab27916d
    vm-name-label ( RO): fedora-34
         protocol ( RO): RFB
         location ( RO): https://192.168.0.200/console?uuid=9cafacae-afed-5d2f-8614-4440a2b03ef6

I followed the instructions and set the disable_pv_vnc option:

xe vm-param-set uuid=<vm_uuid> other-config:disable_pv_vnc=1

and this is reflected in the vm output:

[21:38 localhost ~]# xe vm-list uuid=2909abd6-3bf1-9bde-21d7-d6fcab27916d params=other-config

other-config (MRW)    : disable_pv_vnc: 1; base_template_name: Other install media; import_task: OpaqueRef:45066b0f-ff0e-4e4b-be47-2835ffa83b32; mac_seed: 5920411e-74ad-3a6c-4054-c89645e8a905; install-methods: cdrom

however, (after rebooting), I'm still not seeing VT100 mode as the console protocol:

 [21:40 localhost ~]# xe console-list vm-uuid=2909abd6-3bf1-9bde-21d7-d6fcab27916d
uuid ( RO)             : 9cafacae-afed-5d2f-8614-4440a2b03ef6
          vm-uuid ( RO): 2909abd6-3bf1-9bde-21d7-d6fcab27916d
    vm-name-label ( RO): fedora-34
         protocol ( RO): RFB
         location ( RO): https://192.168.0.200/console?uuid=9cafacae-afed-5d2f-8614-4440a2b03ef6

The vm params are here:
vm_params_output.txt

Any suggestions on howto get this working?

Thanks

olivierlambert

Hmm to be fair, I'm not entirely sure this might work out of the box (ie without guest cooperation) on a HVM guest.

But it is more trivial for a PV guest.

Forza

Could you set up netconsole with your guest. This is a kernel feature that allows you to send the console to a netcat/nc client over the network. You add the configuraton to the kernel command line.

https://www.kernel.org/doc/html/latest/networking/netconsole.html