X-Windows help!

[chilli]

Ok, so all was going well this evening.

 

CentOS 4.4, partition and install = OK

 

Startup and configure = OK

 

Update my cygwin installs = OK

 

Update OpenSSH = Ok

 

Connect via ssh = OK

 

try to run a remote xterm over an ssh connection = NO GO!

 

help, I thought I could suss it out but now I'm tired and I give in

 

I connect to the new server using something like:

 

ssh -X -l username host

 

seems good

 

then I try xterm& and it fails with:

 

xterm Xt error: Can't open display:

 

I've tried changing the sshd_config to enable x11 forwarding and tcp forwarding

 

I've been into the settings for the server logon screen and enabled

XDMCP

 

and I've unchecked the "always disallow tcp connections to x server..."

 

but still no go

 

when logged in the DISPLAY variable is still set to blank, I thought this should be filled in automatically

 

any ideas what is up?

 

Should post on an IT forum really, just I know there are a fair few IT bods on here, any pointers much appreciated. First time I've used centos and I'm not sure if I'm missing something obvous...

[Wez]

type export DISPLAY=0,0 in your ssh term and try again.

 

If that doesnt work try export DISPLAY=host ip:0,0 and sub host ip for the client you have ssh from eg :-

 

export DISPLAY=192.168.10.1:0,0

 

[Todd]

you could always try adding more milk and beating it with a fork, then put it back in the oven for 20mins at gas mark 4.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Other than that, I aint got a bloody clue what your on about

[chilli]

type export DISPLAY=0,0 in your ssh term and try again.

 

If that doesnt work try export DISPLAY=host ip:0,0 and sub host ip for the client you have ssh from eg :-

 

export DISPLAY=192.168.10.1:0,0

 

 

hmmm just given that a quick try with no luck.

 

I've already got a vnc connected (x is started) so does that mean 0,0 is not available anyway? do I need to create a new display?

 

hmmm going to have to do more battle with this tomorrow.

 

seem to remember doing this with RH9 wasn't so troublesome, but I've probably forgotten something, it's been a while

[Wez]

Try doing it using two commands :-

 

$DISPLAY=192.168.10.1:0.0

$export DISPLAY

 

I cant remember if its supposed 0,0 or 0.0 so give both a try.

 

Failing that google for exporting X displays

[chilli]

still stuck

 

I tend to get errors of the form:

 

[louis@linux1 ~]$ xterm Xt error: Can't open display:

[louis@linux1 ~]$ export DISPLAY=192.168.1.2:0.0

 

if I run

 

ssh -X -l louis 192.168.1.10

 

and optionally seting the $DISPLAY variable here (it defaults as blank which doesn't seem right)

 

and then

 

xterm&

 

not sure in cygwin if I'm supposed to run startx first, I've tried with and without

 

I've also added the ip to X access control using

 

xhosts INET:192.168.1.2

 

on the server, still no go

 

I give up, maybe I should drop cygwin and try something like xmin or something? Although downloading xmin seems impossible, really slow connection or something their end...

[carl0s]

Try doing it using two commands :-

 

$DISPLAY=192.168.10.1:0.0

$export DISPLAY

 

I cant remember if its supposed 0,0 or 0.0 so give both a try.

 

Failing that google for exporting X displays

 

It's 0.0

[carl0s]

The problem probably lies in your cygwin config. I assume you're wanting the X clients to use your windows machine as the X server?

 

Have a look at NX. You'll be very impressed. It's on a par with MS's Terminal Services.

[carl0s]

NX as a finished product wasn't free, but the underlying code was GPL'd so freenx was developed. I've used this and it's very good. As of some time ago though, NoMachine released the desktop version of NX as free (as in beer).

[chilli]

thanks for the help.

 

tried xmin - failed

 

tried nx client, created a gnome session and it did some stuff then reported:

 

NX> 203 NXSSH running with pid: 2436

NX> 285 Enabling check on switch command

NX> 285 Enabling skip of SSH config files

NX> 285 Setting the preferred NX options

NX> 200 Connected to address: 192.168.1.10 on port: 22

NX> 211 The authenticity of host '192.168.1.10 (192.168.1.10)' can't be established.

RSA key fingerprint is 58:62:c8:57:1c:a4:ad:39:11:c6:53:51:05:a9:a1:95.

Are you sure you want to continue connecting (yes/no)?

Warning: Permanently added '192.168.1.10' (RSA) to the list of known hosts.

NX> 202 Authenticating user: nx

NX> 208 Using auth method: publickey

NX> 204 Authentication failed.

 

--

 

which is kind of inline with some of the xterm errors I was getting which basically say

 

xlib doesn't know what protocol to use

 

which I think is a similar access/security setting problem on the server.

 

I've disabled the firewall and security on the server, not sure what the issue is but does any of that info help?

[carl0s]

thanks for the help.

 

tried xmin - failed

 

tried nx client, created a gnome session and it did some stuff then reported:

 

NX> 203 NXSSH running with pid: 2436

NX> 285 Enabling check on switch command

NX> 285 Enabling skip of SSH config files

NX> 285 Setting the preferred NX options

NX> 200 Connected to address: 192.168.1.10 on port: 22

NX> 211 The authenticity of host '192.168.1.10 (192.168.1.10)' can't be established.

RSA key fingerprint is 58:62:c8:57:1c:a4:ad:39:11:c6:53:51:05:a9:a1:95.

Are you sure you want to continue connecting (yes/no)?

Warning: Permanently added '192.168.1.10' (RSA) to the list of known hosts.

NX> 202 Authenticating user: nx

NX> 208 Using auth method: publickey

NX> 204 Authentication failed.

 

--

 

which is kind of inline with some of the xterm errors I was getting which basically say

 

xlib doesn't know what protocol to use

 

which I think is a similar access/security setting problem on the server.

 

I've disabled the firewall and security on the server, not sure what the issue is but does any of that info help?

 

erm, you have to install the nxserver as well..

and then do some importing of keys from the server into your client.

Bear in mind that nxserver and nxclient are the reverse terminology of X server and client. e.g. in X, the server is the output display (your windows computer), and the client is the application (on the linux box) that you want presented on the display. With nx, the nxserver runs on the Linux machine, and the nxclient is what you use for connecting, just like Remote Desktop Client, tsclient, vnc client, Citrix ICA client etc.

 

best to follow the installation guide or some howto.

[chilli]

ahhh right, me stupid, I thought it talked directly to the x server or something, will have a try of that then

 

cheers

[chilli]

strangely enough it does seem to work if I use

 

XWin :0 -query remote_hostname_or_ip_address_0

 

just tried it and it spawned me a new desktop, I logged in and it fired up...

 

just that this doesn't work over the ssh connection

[chilli]

Update!

 

Ok think I've got it sussed for what I want to do at the moment.

 

firstly I think it was originally working, just the client x server wasn't running properly. I've had that working since.

 

But what I really wanted was a screen that behaves like you are sat at the actual machine as a new user...

 

and I found this article http://www.macosxhints.com/article.php?story=20041117115414383

 

which explains how to use XDMCP over SSH (rather than just X11 forwarding).

 

it's so simple but perfect for what I need.

 

in a nutshell I just do:

 

cygwin:

 

startx

ssh -X remote.host

Xnest :1 -geometry 1280x810 -query localhost

 

easy!

 

I had to install xnest on the server of course and set XDMCP settings up... and I played with a few other things.

 

that will do me for the moment.

 

also got VNC going but it starts with a blank x and a terminal, not so user friendly

 

impressed by CentOS4.4 and yum so far.

 

Now I can configure my servers from the comfort of the front room and the laptop, lovely

 

thanks for all the help guys

 

and I'll have a further play with freenx/nxserver another day, got it all installed, just got stuck configuring the server end

[Wez]

I just finished getting fedora 6 working on Dell GX260 with intel onboard video chipset, what a complete pain in the @rse, all installed ok but X would not run, turned out I needed a BIOS update along with the latest version of the intel X drivers.

 

All working now though, 3D accel at 1280x1024 32bit

[chilli]

Nice one. I must admit Centos4.4 went on like a breeze, video and X and everything I have FC6 here too but I wanted to use CentOS as it is a potential server at some stage.

 

nice when it all starts working isn't it, can be a battle at times though. I remember with earlier RedHat doing battle to try and get the graphics working and X to start - usually a few beers helped in the end

[carl0s]

I just finished getting fedora 6 working on Dell GX260 with intel onboard video chipset, what a complete pain in the @rse, all installed ok but X would not run, turned out I needed a BIOS update along with the latest version of the intel X drivers.

 

All working now though, 3D accel at 1280x1024 32bit

 

Have you installed Compiz or Beryl yet? It's working a treat here through AIGLX and it's really rather trick

[Wez]

Have you installed Compiz or Beryl yet? It's working a treat here through AIGLX and it's really rather trick

 

Nope not tried them yet, Compiz is looking pretty slick though

[Wez]

nice when it all starts working isn't it, can be a battle at times though. I remember with earlier RedHat doing battle to try and get the graphics working and X to start - usually a few beers helped in the end

 

I agree, although if I had another video card it would not have been an issue, the older Dell BIOS didnt have an option to increase the Video memory from 1mb to 8mb, the BIOS update fixed that.

 

Then due to driver issues with the intel chipset I had to upgrade X11 to the latest release as X11 complained the BIOS was returning no video modes available.

[Wez]

Compiz is very slick

[chilli]

so what's compiz then? (sorry for being dumb - just getting back into linux stuff today)

 

first day at new job today, playing with my old friend Java again tomcat, ant etc quite nice, my last job was a bit specialist embedded and a lot was C only, bit dull by comparison

[carl0s]

Compiz is very slick

 

Extremely.

 

Beryl is the 'fork' run by people who want more bells and whistles with slightly less regard for cleanliness of code/testing etc.

 

Installing Beryl on Ubuntu was a piece of cake, once Xorg was configured for DRI and AIGLX properly.

 

With your Intel card you should be able to do AIGLX I would've thought (due to there probably being an open source driver available), although performance might not be great.

 

Newer ATI and nVidia cards have to use Xgl which is a full X server replacement running in OpenGL, whilst AIGLX allows OpenGL functions to sort of take over small areas of the screen at a time, kind of. So AIGLX is the preferred route at the moment, just that nVidia and ATI's own proprietry drivers don't support it. Older ATI gear like my Mobility Radeon 7500 in the Thinkpad is fine because these are supported by the open source Xorg ATI driver ("radeon").

 

Once X is configured properly, just run "beryl-manager" to fire it up. If it works well then add it to the gnome session startup list in preferences -> sessions -> startup items (or whatever it was..)

[carl0s]

so what's compiz then? (sorry for being dumb - just getting back into linux stuff today)

 

first day at new job today, playing with my old friend Java again tomcat, ant etc quite nice, my last job was a bit specialist embedded and a lot was C only, bit dull by comparison

 

I think there are some good Compiz/Beryl demonstrations on YouTube. Novell were the first to demo it I think, since the creator of Compiz is a Novell employee.