Bug#966510: gnome-boxes: guest gets no Internet if host connects through VLAN

[Roman Riabenko]

Package: gnome-boxes
Version: 3.36.5-1
Severity: normal

Dear Maintainer,

*** Reporter, please consider answering these questions, where appropriate ***

   * What led up to the situation?
Create a virtual machine with gnome-boxes on a laptop.
Gnome-boxes configures Internet connection for the guest automatically.
Move laptop to a network which is configured with VLAN tagging.
The guest OS gets no Internet connection.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?
If the host has connection from VLAN-tagged network and a different
network at the same time, the guest OS gets Intrenet connection.

I tried connecting to different networks (Ethernet, WiFi, Buletooth).
The guest OS gets Internet all the time, except for this one network,
which the administrator told me is VLAN-configured to separate
the guest WiFi network from the office internal network.

I tried Windows 10 and Debian guests with the same result.

It was suggested to me that VLAN may drop frames from the VM
because VM has different MAC address. I wanted to look into
ebtables whether i can use ebtables to change the MAC, but gave up
for now.

   * What was the outcome of this action?
The guest OS gets no Internet on one network, 
which the adminstrator said me is VLAN-tagging traffic.
I perceive it as gnome-boxes suddenly not working because
I rely on gnome-boxes to configure the guest OS connection.

   * What outcome did you expect instead?
I expected gnome-boxes to "just work" and make the VM traffic appear
coming from the host, so it is treated the same as the host traffic.
I belive it comes within the scope of gnome-boxes to make configuration
easy for the end user.

*** End of the template - remove these template lines ***


-- System Information:
Debian Release: bullseye/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 5.7.0-1-amd64 (SMP w/4 CPU threads)
Kernel taint flags: TAINT_WARN, TAINT_FIRMWARE_WORKAROUND
Locale: LANG=uk_UA.UTF-8, LC_CTYPE=uk_UA.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages gnome-boxes depends on:
ii  dconf-gsettings-backend [gsettings-backend]  0.36.0-1
ii  genisoimage                                  9:1.1.11-3.1
ii  libarchive13                                 3.4.3-1+b1
ii  libc6                                        2.31-2
ii  libcairo2                                    1.16.0-4
ii  libfreerdp2-2                                2.1.2+dfsg1-2
ii  libgdk-pixbuf2.0-0                           2.40.0+dfsg-5
ii  libglib2.0-0                                 2.64.4-1
ii  libgtk-3-0                                   3.24.20-1
ii  libgtk-vnc-2.0-0                             1.0.0-1
ii  libgudev-1.0-0                               233-1
ii  libosinfo-1.0-0                              1.7.1-1
ii  libosinfo-bin                                1.7.1-1
ii  libpango-1.0-0                               1.44.7-4
ii  libsecret-1-0                                0.20.3-1
ii  libsoup2.4-1                                 2.70.0-1
ii  libspice-client-glib-2.0-8                   0.38-2
ii  libspice-client-gtk-3.0-5                    0.38-2
ii  libtracker-sparql-2.0-0                      2.3.4-1+b1
ii  libusb-1.0-0                                 2:1.0.23-2
ii  libvirt-daemon                               6.4.0-2
ii  libvirt-glib-1.0-0                           3.0.0-1
ii  libvte-2.91-0                                0.60.3-1
ii  libwebkit2gtk-4.0-37                         2.28.3-2
ii  libwinpr2-2                                  2.1.2+dfsg1-2
ii  libxml2                                      2.9.10+dfsg-5+b1
ii  tracker                                      2.3.4-1+b1

Versions of packages gnome-boxes recommends:
ii  qemu-system-x86  1:5.0-13

gnome-boxes suggests no packages.

-- no debconf information