Ubuntu 18-04 : no veyon service when user logs in

zeltron80

Hi

The issue happens with Ubuntu mate 18-04, Veyon installed from ppa (4.1.7-1)

The problem is :
In veyon master, I can see the client PCs when no user is logged (I see lightdm login screen, and I can take control of the PC).
But as soon as a user logs in on client, computer becomes "red" in veyon-master, and I can't connect to it anymore.

Below are some informations about tests I did, in case they could be usefull :

Result for "ps aux | grep veyon" on PC, before a user logs in :

root      2313  1.6  0.6 370832 27004 ?        Ssl  10:20   0:00 /usr/bin/veyon-service
root      2531  0.5  0.7 376180 31304 ?        Sl   10:20   0:00 /usr/bin/veyon-server
lightdm   2533  1.3  0.7 513528 32000 ?        Sl   10:20   0:00 /usr/bin/veyon-worker {8e997d84-ebb9-430f-8f72-d45d9821963d}

Result for "ps aux | grep veyon" on PC, after testuser has logged in :

root      2313  0.5  0.6 370832 27008 ?        Ssl  10:20   0:00 /usr/bin/veyon-service
testuser  2814  1.6  1.1 736420 47364 ?        Sl   10:22   0:00 /usr/bin/veyon-worker {8e997d84-ebb9-430f-8f72-d45d9821963d}

Of course, I add a veyon-svc.desktop file in /etc/xdg/autostart/, which launches veyon-ctl service start.
I got popup windows (2 or 3) at session start, asking for root password. Typing the root password didn't change anything.

I tried to add those lines in /etc/sudoers too ("Etudiants" and "Utilisateurs" are LDAP groups containing all my users) :

Cmnd_Alias VEYON_CMDS = /usr/bin/veyon-server start, /usr/bin/veyon-ctl service start, /usr/bin/veyon-service -quiet -startservice
%Etudiants ALL=(ALL) NOPASSWD: VEYON_CMDS
%Utilisateurs ALL=(ALL) NOPASSWD: VEYON_CMDS

Nothing changes ( in fact, the only change was I only got one popup window for root password)

I tried to use command line in user session to see what it did :

Result for sudo veyon-ctl service start :

QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
No protocol specified
qt.qpa.screen: QXcbConnection: Could not connect to display :0.0
Could not connect to any X display.

Result for : sudo /usr/bin/veyon-service -quiet -startservice :

2019-03-26T11:27:16.167: [WARN] Environment for session "/org/freedesktop/login1/session/c4" not yet available - retrying in 1000 msecs

(looping message)

Just for the record : I'm not new to Veyon : I already use it with ubuntu 16-04 and .deb veyon 4.0.4 package, and in other Win10 rooms. They work fine.

Have you got a solution for me ?

Thanks for your job
ET

zeltron80

Hi,

Waiting for an answer, I red these pages :
https://veyon.io/blog/2018/04/09/systemd-support/
https://github.com/veyon/veyon/issues/305

I adapted my installation method/configuration, but always the same issue (I tried veyon_4.1.91-ubuntu-bionic_amd64.deb too).

On the blog page (which, I'm conscient, is a little bit "old"), you talk about veyon-server and veyon-service, but nothing about this veyon-worker I can see in 'ps aux' when a user logs in.

But what I can see, is that veyon server disappears from processes list when a user is looged in (probably the cause for the issue).

Can anybody tell me if he managed to get veyon working with ubuntu 18-04 ? I'm preparing my room's configuration for next academic year, and I really need to know if I can count on veyon or not.
I must confess, I'm a little bit worried

Thanks
ET

zeltron80

A little precision (maybe useful ?) :

It seems to work fine for lightdm user :
As we can see in my previous posts, when PCs are on login screen (no user logged in), we can see three processes :

root      2313  1.6  0.6 370832 27004 ?        Ssl  10:20   0:00 /usr/bin/veyon-service
root      2531  0.5  0.7 376180 31304 ?        Sl   10:20   0:00 /usr/bin/veyon-server
lightdm   2533  1.3  0.7 513528 32000 ?        Sl   10:20   0:00 /usr/bin/veyon-worker {8e997d84-ebb9-430f-8f72-d45d9821963d}

I suppose it's exactly what we should see with a logged user.
If I try

service veyon-service start

In my user session, it asks for root password.

zeltron80

OK,

I finally found where the issue comes from :

My users home directory are on an NFS server. The local root account has no rights on their home.
I suppose veyon tries to write something in user's home, and that's why it fails starting service.

Could you give me some details about this, so I could try to find a way to make it work ?

Thanks
ET

zeltron80

Hi,

I will stop discussion on this post, as the problem is "resolved".
But I'l make a new one about NFS, because I really need to get informations about this to make it work in my rooms

ET

tobydox

Sorry for the confusion. Even though the figures at http://docs.veyon.io/en/latest/admin/introduction.html#components are outdated the information below are up to date and should give you an idea of the involved processes. Do you still have questions regarding the processes?

Veyon Community Forum

Ubuntu 18-04 : no veyon service when user logs in