running 20.2 XFCE with virtual VNC Desktop - not showing password prompts

[T_lancer]

I am running 20.2 XFCE on a headless server. However I still wish to have a Desktop from time to time, so I setup a virtual VNC desktop using this guide: https://linuxhint.com/installing_vnc_server_linux_mint/

Everything is mostly fine, it seemed to have reset the default XFCE environment and looks like the one in the guide, rather than the Linux Mint default XFCE environment. However I do not receive password prompts when running this desktop. Password prompts for the Update manager for example. Or When trying to load synaptic package manager. I receive no password prompt and the application does not load.

So the question is, why is this not working properly. What must I configure the get the normal behaviour back?

perhaps it is related to the XFCE configuration?



fixed it.

[Hercules]

This is exactly my problem. Could you explain how you fixed it ?

[T_lancer]

not surprising. I have found these forums to be rather useless at anything that isn't a easy google search away anyway.

my edit was more out of protest for that reason.

The only "solution" I found was to no longer run headless. be that with an unused screen attached or a dummy screen.

[Hercules]

not surprising. I have found these forums to be rather useless at anything that isn't a easy google search away anyway.

my edit was more out of protest for that reason.

The only "solution" I found was to no longer run headless. be that with an unused screen attached or a dummy screen.

Thanks for responding, btw.

Do I understand that by attaching a monitor to the target computer, the passwords would appear on the VNC client?

[Hercules]

Can anyone confirm that they do get password prompts when they try to update the software via the VNC GUI?

Maybe it has never worked

[Hercules]

For info:

Code: Select all

System:    Kernel: 5.4.0-80-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 Desktop: Xfce 4.16.0 tk: Gtk 3.24.20 
           info: xfce4-panel wm: xfwm4 dm: LightDM 1.30.0 Distro: Linux Mint 20.2 Uma base: Ubuntu 20.04 focal 
Machine:   Type: Desktop Mobo: ASUSTeK model: P6X58D-E v: Rev 1.xx serial: <filter> BIOS: American Megatrends v: 0803 
           date: 08/06/2012 
CPU:       Topology: Quad Core model: Intel Core i7 950 bits: 64 type: MT MCP arch: Nehalem rev: 5 L2 cache: 8192 KiB 
           flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 49180 
           Speed: 1603 MHz min/max: 1600/3068 MHz boost: enabled Core speeds (MHz): 1: 1606 2: 1605 3: 1630 4: 1631 5: 1607 
           6: 1621 7: 1656 8: 1638 
Graphics:  Device-1: NVIDIA GF110 [GeForce GTX 570] vendor: CardExpert driver: nvidia v: 390.144 bus ID: 03:00.0 
           chip ID: 10de:1081 
           Display: server: AT&T Laboratories Cambridge X.org 1.20.11 driver: nvidia unloaded: fbdev,modesetting,nouveau,vesa 
           tty: N/A 
           OpenGL: renderer: N/A v: N/A direct render: N/A 
Audio:     Device-1: Intel 82801JI HD Audio vendor: ASUSTeK driver: snd_hda_intel v: kernel bus ID: 00:1b.0 chip ID: 8086:3a3e 
           Device-2: NVIDIA GF110 High Definition Audio vendor: CardExpert driver: snd_hda_intel v: kernel bus ID: 03:00.1 
           chip ID: 10de:0e09 
           Sound Server: ALSA v: k5.4.0-80-generic 
Network:   Device-1: Marvell 88E8056 PCI-E Gigabit Ethernet vendor: ASUSTeK driver: sky2 v: 1.30 port: d800 bus ID: 05:00.0 
           chip ID: 11ab:4364 
           IF: enp5s0 state: up speed: 1000 Mbps duplex: full mac: <filter> 
           IF-ID-1: docker0 state: down mac: <filter> 
Drives:    Local Storage: total: 465.76 GiB used: 21.35 GiB (4.6%) 
           ID-1: /dev/sde vendor: Samsung model: SSD 860 EVO 500GB size: 465.76 GiB speed: 6.0 Gb/s serial: <filter> rev: 4B6Q 
           scheme: MBR 
Partition: ID-1: / size: 456.95 GiB used: 21.35 GiB (4.7%) fs: ext4 dev: /dev/sde5 
Sensors:   System Temperatures: cpu: 45.0 C mobo: N/A 
           Fan Speeds (RPM): N/A 
Repos:     No active apt repos in: /etc/apt/sources.list 
           Active apt repos in: /etc/apt/sources.list.d/additional-repositories.list 
           1: deb [arch=amd64] https://download.docker.com/linux/ubuntu focal stable
           Active apt repos in: /etc/apt/sources.list.d/google-chrome.list 
           1: deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main
           Active apt repos in: /etc/apt/sources.list.d/official-package-repositories.list 
           1: deb http://packages.linuxmint.com uma main upstream import backport #id:linuxmint_main
           2: deb http://archive.ubuntu.com/ubuntu focal main restricted universe multiverse
           3: deb http://archive.ubuntu.com/ubuntu focal-updates main restricted universe multiverse
           4: deb http://archive.ubuntu.com/ubuntu focal-backports main restricted universe multiverse
           5: deb http://security.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
           6: deb http://archive.canonical.com/ubuntu/ focal partner
Info:      Processes: 254 Uptime: 1h 00m Memory: 9.72 GiB used: 723.7 MiB (7.3%) Init: systemd v: 245 runlevel: 5 Compilers: 
           gcc: 9.3.0 alt: 9 Shell: bash v: 5.0.17 running in: xfce4-terminal inxi: 3.0.38

[Hercules]

Ok, a bit of research.

• Using the server desktop with a cinnamon session :
  
  2 policy kits running
  ../policy-kit-1 <= seen via SSH before GUI login
  ../policy-kit-1-gnome <= seen after GUI login, process started by cinnamon-session
  
  Running synaptic-pkexec via server GUI terminal CLI <= GUI prompts for password, all works fine
• Using the server desktop with an xfce session :
  
  2 policy kits running
  ../policy-kit-1 <= seen via SSH before GUI login
  ../policy-kit-1-gnome <= seen after GUI login, process started by xfce4-session
  
  Running synaptic-pkexec via vnc server GUI terminal CLI <= GUI prompts for password, all works fine
• Using the vnc remote desktop with an xfce session :
  
  1 policy kit running
  ../policy-kit-1 <= seen via SSH before GUI login
  ../policy-kit-1-gnome <= This is missing
  
  Running synaptic-pkexec via vnc GUI terminal CLI<= prompts for password on CLI, fails with "GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie"

This suggests to me that the policy-kit-gnome is required for the password prompts to work, but the systemd started vncserver fails to run this component.

I found this post that asserted that the password prompts did occur if the vncserver was started from the CLI (this I have confirmed), or using a sneaky bit of systemd entry to run by SSH command line.

Now this all well and good, but I don't know enough about GUI processes to work out how to get the policy-kit1-gnome to be run by the systemd process?

For now, I'll either just run the vncserver with a local script, or maybe attempt the sneaky SSH approach in systemd.

All thoughts welcome