xhost

In my home, I have two laptops connected to each other in
a mini network with fixed addresses. These are the entries
in my /etc/hosts:

192.168.0.4 sony.ariannuccia.zz sony
192.168.0.5 vobis.ariannuccia.zz vobis

The netmask is 255.255.255.248 (equivalent to /29).

So far, i.e. under SuSE Linux 8.1 and KDE 3.0.3, I had no problems
with opening a KDE window of one computer in the other one.

Two days ago, I installed SuSE Linux 9.1 and KDE 3.2.1, so far on
"vobis" only. Now, I have the problem that I cannot open "sony"
clients in "vobis" any more.

Obviously, the xhost settings are ignored by the new installation
on "vobis". Even when I disable all controls by typing "xhost +",
no "sony" client can be opened in "vobis", though the system
replies correctly: "access control disabled, clients can connect
from any host." But that is a lie.

Thanks in advance for your help,
Wolfgang



Wolfgang Mueller

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In comp.os.linux.networking Wolfgang Mueller <(E-Mail Removed)> suggested:
> In my home, I have two laptops connected to each other in
> a mini network with fixed addresses. These are the entries
> in my /etc/hosts:
[..]

> Two days ago, I installed SuSE Linux 9.1 and KDE 3.2.1, so far on
> "vobis" only. Now, I have the problem that I cannot open "sony"
> clients in "vobis" any more.

Instead of mucking around with 'xhost', try connecting with
'ssh -C -X hostname', start 'xclock' and see if this works
better. (You can try using the IP, if there are problems with
using the hostname.) Presuming sshd is installed and running,
should be per default.

Good luck

--
Michael Heiming (GPG-Key ID: 0xEDD27B94)
mail: echo (E-Mail Removed) | perl -pe 'y/a-z/n-za-m/'
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Wolfgang Mueller <(E-Mail Removed)> wrote:

> So far, i.e. under SuSE Linux 8.1 and KDE 3.0.3, I had no problems
> with opening a KDE window of one computer in the other one.

Hmm, doesn't SuSE have a default firewall? Does 'iptables -L' show
anything in the firewall?

--
Cameron Kerr
(E-Mail Removed) : http://nzgeeks.org/cameron/
Empowered by Perl!

On Sun, 23 May 2004 13:23:48 +1200, Cameron Kerr wrote:
>
> On Sat, 22 May 2004 11:16:18 +0200, Wolfgang Mueller wrote:
> >
> > So far, i.e. under SuSE Linux 8.1 and KDE 3.0.3,
> > I had no problems with opening a KDE window of
> > one computer in the other one.
>
> Hmm, doesn't SuSE have a default firewall?

Obviously it has. In the "Simple Mode" of Yast run level
editor, there are listed three firewall services:

*************************************************
Service Enabled Description
SuSEfirewall2_final No SuSEfirewall2 phase 3
SuSEfirewall2_init No SuSEfirewall2 phase 2
SuSEfirewall2_setup No SuSEfirewall2 phase 1
*************************************************

So far, I thought everything was ok. But I underestimated SuSE
people's trickiness, because listing the same services in the
so-called "Expert Mode" shows a quite different result:

************************************************** *****************
Service Running B 0 1 2 3 4 5 6 S Description
SuSEfirewall2_final Yes SuSEfirewall2 phase 3
SuSEfirewall2_init Yes SuSEfirewall2 phase 2
SuSEfirewall2_setup No SuSEfirewall2 phase 1
************************************************** *****************

So, after each reboot, I have to drop the first two services
manually. But that does not help; the system continues to refuse any
attempt to open a remote X client.

> Does 'iptables -L' show anything in the firewall?

That's what it shows:

************************************************** ***
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination
************************************************** ***

There is one more interesting detail that perhaps helps you for a
diagnosis of the error. Not only a remote user, but even a local
user different from the KDE owner cannot open an X client as long as
xhost control is enabled. But in this case disabling it by 'xhost +'
helps, whereas for a remote user it does not work.

Thanks so far for your help.

Wolfgang

Wolfgang Mueller wrote:
> There is one more interesting detail that perhaps helps you for a
> diagnosis of the error. Not only a remote user, but even a local
> user different from the KDE owner cannot open an X client as long as
> xhost control is enabled. But in this case disabling it by 'xhost +'
> helps, whereas for a remote user it does not work.

For me it seams that the X server doesn't allow incomming connection for
other protcols than the local one's (socket family PF_LOCAL).
Asuming you are running kdm as your default display manager, you maybe
take a look at your kdm configuration file at /etc/kde3/kdm/Xservers and
search for a line like:

:0 local@tty1 /usr/X11R6/bin/X :0 -dpi 75 -nolisten tcp vt7

and change it to:

:0 local@tty1 /usr/X11R6/bin/X :0 -dpi 75 vt7

Now the server also listens for incomming TCP connection requests.

For me this work's fine. Hope this helps you too.


Mathias

On Sun, 23 May 2004 22:56:15 +0200, Mathias Krause wrote:
>
> On Sun, 23 May 2004 12:39:01 +0200, Wolfgang Mueller wrote:
> >
> > There is one more interesting detail that perhaps helps you for a
> > diagnosis of the error. Not only a remote user, but even a local
> > user different from the KDE owner cannot open an X client as long
> > as xhost control is enabled. But in this case disabling it by
> > 'xhost +' helps, whereas for a remote user it does not work.
>
> For me it seams that the X server doesn't allow incomming
> connection for other protcols than the local one's (socket family
> PF_LOCAL). Asuming you are running kdm as your default display
> manager, you maybe take a look at your kdm configuration file at
> /etc/kde3/kdm/Xservers and search for a line like:
>
> :0 local@tty1 /usr/X11R6/bin/X :0 -dpi 75 -nolisten tcp vt7
>
> and change it to:
>
> :0 local@tty1 /usr/X11R6/bin/X :0 -dpi 75 vt7
>
> Now the server also listens for incomming TCP connection requests.
>
> For me this work's fine. Hope this helps you too.

First I had some difficulty to find the file /etc/kde3/kdm/Xservers;
but then I found it in a different directory: /etc/X11/xdm/Xservers.
Editing this file the way you specified and rebooting the computer
definitely solved my problem. Now, I can open any remote X client.

Thank you very much,
Wolfgang

Wolfgang Mueller wrote:
> First I had some difficulty to find the file /etc/kde3/kdm/Xservers;
> but then I found it in a different directory: /etc/X11/xdm/Xservers.

So you are running xdm as your default display manager
Of course this one has it's own configuration file.

> Editing this file the way you specified and rebooting the computer
> definitely solved my problem. Now, I can open any remote X client.
> Thank you very much,

No problem. But just restarting the X server would also have done the
trick.


Mathias

On Mon, 24 May 2004 13:39:46 +0200, Mathias Krause wrote:
>
> On Mon, 24 May 2004 13:12:03 +0200, Wolfgang Mueller wrote:
> >
> > Editing this file the way you specified and rebooting the computer
> > definitely solved my problem. Now, I can open any remote X client.
> > Thank you very much,
>
> No problem. But just restarting the X server would also have
> done the trick.

I thought so too. But restarting the X server was not sufficient.
Obviously, SuSE 9.1 is much more tricky than we believe.

Thanks again,
Wolfgang