On 2020-06-10 4:18 p.m., Dave Voutila wrote:
George writes:
Hi guys,
I apologize if this maybe out of topic even though it is truly related
to VMM than Debian.
I am trying to setup a VMM Debian based guest but I'm not able to get
it to work. I found some description on the web about which settings
to edit in grub.cfg to enable the serial console and created a VM with
10.3 in qcow2 disk format in KVM. Now I am trying to start the same on
OpenBSD 6.7 but keep getting the connected message and then just
"Rebooting " after I hit some keyboard keys seems like baud rate issue
but not sure.
Not baudrate related, but there are some known issues in OpenBSD 6.7
related to the emulated uart device in vmd(8). (I have a patch if you
follow -current[1] that fixes stability issues.)
Oh-oh didn't know of those :). No I am not following current, unfortunately.
My advice is to install using vmm(4)/vmd(8) and not migrate an image
from KVM. I believe Debian started including the virtio cdrom drivers
finally...but, if not, google for some guides on adding those to the
iso.
This sounds good, will try it next.
Make sure you install OpenSSH and rely on ssh(1) connections to the guest.
As soon as you can, modify the grub defaults in /etc/default/grub and
set the GRUB_CMDLINE_LINUX_DEFAULT to include:
tsc=reliable tsc=noirqtime console=ttyS0,115200
Make sure to run update-grub afterwards.
You mean grub-mkconfig?
You'll probably have a bad time with your clock, though Debian use a 4.x
kernel, so it won't be too bad and may manage using tsc as a
clocksource. Otherwise expect refined-jiffies as the clocksource and it
may run at a rate of 50% of host time.
I wish I could get to that point... hehe. Does this mean that the CPU
will tick at a rate half the main processor? That means performance /2
...???
I recommend you also build and install my Linux clone of vmmci(4)[2]
within the Debian guest if you want safe guest shutdowns.
Will do once I get there.
After messing with it for a while now I am getting a new error:
vmctl: could not open disk image(s)
even thought the disk is there and readable to the user I have setup
in vm.conf in fact I have another VM with the same configuration and
disk with the same permissions and in the same location that works (it
is OpenBSD based).
Use top(1) showing threads and command line args: top -C -g vmd
Chances are you have a lingering vmd(8) process for the Debian guest
using the disk. Kill -9 the one with the vm name.
That is an excellent point never checked...
I would greatly appreciate it if someone has gone this path and can
share some config info with me.
Cheers and thanks in advance,
George
[1] https://sisu.io/patches/vmd-thread-safety-07062020-v1.patch
[2] https://github.com/voutilad/virtio_vmmci
Thanks Dave, this is really appreciated. You have given me more
information to go on.
Cheers,
George
-Dave
