Libvirt issue in RHEL 8.6 with VNC

Community Support General
1

Hi

I’m not sure if someone else has tested rhel 8.6 or the latest libvirt version, we did in our testing cluster and we found an issue with libvirt 8.0.0 (we are running OpenNebula 6.4 in our testing cluster).

This is the error that we get trying to migrate a VM from a 8.4 hyp to 8.6:

unsupported configuration: VNC password is 64 characters long, only 8 permitted Could not migrate xxxxx

Indeed in our default VM templates we have:

GRAPHICS=[
  LISTEN="0.0.0.0",
  RANDOM_PASSWD="YES",
  TYPE="VNC" ]

and this behaviour was changed from libvirt (https://gitlab.com/libvirt/libvirt/-/commit/27c1d06b5bd68bdce55efff0a50a15a30cb2a96b)

Someone else had this issue with rhel 8.6 or centos stream? maybe OpenNebula devs are already aware of this, do you have any workaround? In our case we have tried to use SPICE from a new VM and that works, but we prefer to keep VNC.

Cheers and thanks!
Álvaro

2

Apparently the extra chars on a VNC password over 8 chars were silently dropped:

RFC 6143: The Remote Framebuffer Protocol

OpenNebula will honor this in the next release (6.6) as it needs a change in the ‘oned’ daemon.

Honor the VNC password length of (up to) 8 symbols in libvirt/qemu · Issue #5842 · OpenNebula/one · GitHub

3

Hi Tino

Thanks a lot for the update.

Cheers
Álvaro