topic Re: gui commands doesnt works when running via sudo in Operating System - Linux

gui commands doesnt works when running via sudo

Maaz — Sat, 20 Feb 2010 12:02:09 GMT

jodt@tiger:~/Desktop> xhost +
access control disabled, clients can connect from any host
jodt@tiger:~/Desktop> sudo firefox
Error: no display specified
jodt@tiger:~/Desktop> sudo virt-manager
Unable to initialize GTK: could not open display
jodt@tiger:~/Desktop>

only "sudo /sbin/yast2" works, but in TUI(ncurses) mode

all of the above commands works nicely when I did "su - root"

what should I do, please help

Regards
Maaz

Re: gui commands doesnt works when running via sudo

Jupinder Bedi — Sat, 20 Feb 2010 12:21:44 GMT

do as follows

#xhost +

than

# DISPLAY=ip_address:0.0;export DISPLAY

than try and also note ip_address should be of the same machine on which you want to diaplay your gui

Re: gui commands doesnt works when running via sudo

Maaz — Sat, 20 Feb 2010 19:09:15 GMT

Hi Thanks Jupinder Bedi for help

I did followinf
jodt@tiger:~/Desktop> xhost +
jodt@tiger:~/Desktop> DISPLAY=127.0.0.1:0.0; export DISPLAY

but no gain.. same errors.

I am working on this box directly(no network ..ssh etc)

Regards
Maaz

Re: gui commands doesnt works when running via sudo

Emil Velez — Sun, 21 Feb 2010 00:33:14 GMT

Need to set the display

SAM has a restricted sam builder on 11.23 and lower so a non-root user can user their regular id to do system admin tasks in sam.

In 11.31 the system management homepage can be configured to allow a non-root person to do different tasks with their regular userid. This way sudo is not necessary.

Re: gui commands doesnt works when running via sudo

Andrew Cowan — Sun, 21 Feb 2010 10:37:27 GMT

I think that the problem is that Linux is denying you local access to the desktop and not sudo.

I can't find the exact manual page but you have to change one of the 'sysconfig' files to enable local access to the desktop.

Some distributions such as Fedora, Mandriva, and Red Hat, use the prefdm script to decide on the XDMCP server to run. Linux runs the prefdm script that loads â /etc/sysconfig/desktopâ file. The DESKTOP line in â /etc/sysconfig/desktopâ file sets the default desktop environment, which sets the default XDMCP server.

The â /etc/X11/xdm/Xaccessâ file is a configuration file of XDM. You can configure XDM server for remote access. The /etc/X11/xdm/Xaccess file controls access of XDM server. You can make use of an asterisk (*) to provide access of the system to anyone. The * CHOOSER BROADCAST line as displayed on the screen, tells XDM that anyone may request chooser that accepts XDMCP connections

Re: gui commands doesnt works when running via sudo

Maaz — Sun, 21 Feb 2010 10:46:20 GMT

Hi thanks Emil Velez
there is no SAM here, I am using a Linux distro(SUSE 11)

I think SAM is a YaST equivalent in HP-UX

Regards

Re: gui commands doesnt works when running via sudo

Steven Schweda — Sun, 21 Feb 2010 14:32:13 GMT

> Error: no display specified

echo $DISPLAY

> all of the above commands works nicely when
> I did "su - root"

su - root
echo $DISPLAY

What's different?

Re: gui commands doesnt works when running via sudo

Maaz — Sun, 21 Feb 2010 17:24:33 GMT

I would like to clear that, I am not accessing this box remotely, I am working on this directly, logs in via an ordinary account(jodt), then whenever I need to work as root, I try to sudo.

Hi Steven Schweda Thanks for help
jodt@tiger:~/Desktop> sudo firefox
Error: no display specified
jodt@tiger:~/Desktop> echo $DISPLAY
:0.0
jodt@tiger:~/Desktop> su - root
Password:
tiger:~ # echo $DISPLAY
:0.0
tiger:~ #

Hi Andrew Cowan thanks for help
/etc/sysconfig/console, /etc/sysconfig/displaymanager, and /etc/X11/xdm/Xaccess attached.

tiger:~ # grep -v ^# /etc/X11/xdm/Xaccess

* #any host can get a login window

* CHOOSER BROADCAST #any indirect host can get a chooser

tiger:~ # grep -v ^# /etc/sysconfig/displaymanager

DISPLAYMANAGER="gdm"
DISPLAYMANAGER_REMOTE_ACCESS="no"
DISPLAYMANAGER_ROOT_LOGIN_REMOTE="no"
DISPLAYMANAGER_STARTS_XSERVER="yes"
DISPLAYMANAGER_XSERVER_TCP_PORT_6000_OPEN="no"
DISPLAYMANAGER_AUTOLOGIN=""
DISPLAYMANAGER_PASSWORD_LESS_LOGIN="no"
DISPLAYMANAGER_AD_INTEGRATION="no"
DISPLAYMANAGER_SHUTDOWN="auto"
DISPLAYMANAGER_RANDR_MODE_VGA=""
DISPLAYMANAGER_RANDR_MODE_auto="1024x768_60 64.11 1024 1080 1184 1344 768 769 772 795 -HSync +Vsync"
DISPLAYMANAGER_XSERVER="Xorg"

tiger:~ # grep -v ^# /etc/sysconfig/console

CONSOLE_FONT="lat9w-16.psfu"
CONSOLE_UNICODEMAP=""
CONSOLE_SCREENMAP="trivial"
CONSOLE_MAGIC="(K"
FB_MODULES=""
FBSET_PARAMS=""
CONSOLE_ENCODING="UTF-8"

Regards

Re: gui commands doesnt works when running via sudo

Steven Schweda — Sun, 21 Feb 2010 18:32:29 GMT

> jodt@tiger:~/Desktop> sudo firefox
> Error: no display specified
> jodt@tiger:~/Desktop> echo $DISPLAY
> :0.0

That shows what DISPLAY is in your _normal_
environment, _after_ the "sudo xxx" command
has failed. What I'd like to know is what
DISPLAY is _in_ the "sudo" environment.

I don't use sudo, so I know nothing, but if
it doesn't pass through your DISPLAY setting,
then you might try writing a script which
sets DISPLAY and then runs your browser, and
then try running "sudo your_script". Or, for
example, something like:

sudo DISPLAY=':0.0' firefox
or:
sudo firefox --display ':0.0'

"man firefox" seems to do nothing good around
here, but there's some value in:

firefox --help

Most X programs offer a "-display" (or,
apparently, a "--display") option.

man X

Re: gui commands doesnt works when running via sudo

Andrew Cowan — Sun, 21 Feb 2010 18:43:01 GMT

Maaz,

Take a look at these links:

http://www.linuxjournal.com/content/getting-vncserver-running-core-10-gdm

http://www.idevelopment.info/data/Unix/Linux/LINUX_ConfiguringXDMCPRedHatLinux.shtml

Your problem is caused by the GDM security that allows your user to open windows within their own session but it disallows another user, so when you su within a shell, GDM does not see it because it is still running as your user.

Re: gui commands doesnt works when running via sudo

Steven Schweda — Sun, 21 Feb 2010 19:03:31 GMT

> Your problem is caused by [...]

Perhaps, but if so, then "no display
specified" would seem to be a singularly
inappropriate error message.

Re: gui commands doesnt works when running via sudo

Steven Schweda — Sun, 21 Feb 2010 22:26:40 GMT

> man X

That may work better on a real UNIX system
than on a GNU/Linux system.

I still know nothing, but you might try

man sudo

and look for "environment". Apparently,
there are options which affect how
environment variable (like, say, DISPLAY) are
handled. Similarly:

man sudoers

Re: gui commands doesnt works when running via sudo

J. Maestre — Mon, 22 Feb 2010 09:12:08 GMT

How about using gksudo? It should be basically the same, but when dealing with X apps it could make a difference.