Subject: Re: [vserver] XDMCP termial on a vserver: DISPLAY is set to a certain running vserver
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Sun, 27 Nov 2011 02:56:06 +0100

On Sun, Nov 27, 2011 at 12:17:03AM +0100, Ekkard Gerlach wrote:
> Hello, 

> DISPLAY variable is set to a certain running vserver when XDMCP is started 
> on a vserver host by 

>      host:#~/usr/bin/X :1 vt08 -query 192.168.0.100. 

> And not to host. Stopping this certain vserver an DISPLAY variable is
> set correctly to "host.local". Why?

> Background: The vserver in one of my customers office is also used as 
> XDMCP-Terminal (why not?). The XDMCP-Server is a Suse 11.1 machine.
> And it works fine. Now I want to start x11vnc on the vserver to make 
> montoring for support affairs. Using /etc/X11/xdm/Xsetup on the Suse 
> 11.1 XDMCP-Server I inplace the code: 

>     [...]
>     lhost="${DISPLAY/:*/}"
>     host="${lhost/.*/}" 
>     echo lhost: $lhost  "   host:" $host > /tmp/x11vnc_host
>     [...]

> because I want to know "where does the Client come from" to start x11vnc 
> on that remote machine, in my case her its the vserver. If there is
> the vserver "cups" running von the vserver the I get 

>     lhost="cups.local" 
>     host=cups

> When shutdown vserver cups:  vserver cups stop   then I get the right 
> DISPLAY: 
>     lhost="host.local"
>     host=host

> Why? 

> BTW "host" ist not the real name of the vserver, I changed it for better 
> understanding. 

> I've three vservers runing: 
> root@<host>:~# vserver-stat
> CTX   PROC    VSZ    RSS  userTIME   sysTIME    UPTIME NAME
> 91       5 140.1M   3.8M   0m00s95   0m00s62   6d00h17 misc
> 92       6   226M   7.5M   0m00s11   0m00s84  25m31s32 cups  ->   IP 0.92
> 93       8 384.2M  10.3M   0m00s40   0m00s48  17m14s94 samba ->   IP 0.93

> Stopping and starting vserver samba does NOT make samba to
> the favorite vserver which DISPLAY variable is sent, its only
> vserver "cups"! Why is cups the favorite machine on the vserver?

I'm not really following what you are describing here,
please let's start simple with the kernel, patch and
util-vserver version, as well as the setup of 'involved'
guests ....

TIA,
Herbert

> <host>:~# cat /etc/hosts
> [...]
> 192.168.0.100   suse111.local suse111
> 192.168.0.91   misc.local  misc
> 192.168.0.92   cups.local  cups

> <host>:~# /etc/ssh/sshd_config
> [...]
> #ListenAddress 0.0.0.0
> ListenAddress 192.168.0.2    <- thats IP of host vserver 
> Protocol 2
> [...]

> tia
> Ekkard