Not able to export DISPLAY with March 2009, 11.31.

[Narendra Thapa]

This really strange but I am not able to export display with march 2009 11.31.

I am able to export display with other OS before march 2009 but with this particualre OS relase (March 09 11.31) I am not able to do so.

I don't no what to do because in some of the linux (suse)nodes display work fine.


STEPS TO EXPORT DISPLAY:
1. I go to a linux box and export DISPLAY for HP-UX box.

Eg.

ssh -X root@hpuxhost1

With other OS release display is automatically export if I login in the above way or I can export the display after logging in linux box.

Eg.

export DISPLAY=linux1:0.0

But my display is not working with the March 2009 11.31 release and with the same commands I am able to export DISPLAY for other OS release (Eg. other 11.31 release before March 2009 and 11.31 all release.




Its really strange but annoying for me because I really did almost everything but I am not getting what is wrong.

Can anyone please help me out of this. :)

[Narendra Thapa]

It just throws the following message after exporting the DISPLAY:

# xclock
Error: Can't open display:
Error: Couldn't find per display information

[Asif Sharif]

Hi,

Did you install CDE?

Regards,
Asif Sharif

[Narendra Thapa]

I have not install anything extra besides OS installation.

I think CDE is installed by default with the OS or I need to install it manually for March 2009, 11.31.

[Narendra Thapa]

CDE is installed in the machine.

# swlist -l product | grep -i cde
CDE B.11.31 HP-UX CDE User Interface

[Turgay Cavdar]

Check if dtlogin is running:
ps -ef | grep dtlogin

If not enable it with:
/usr/dt/bin/dtconfig -e

And then start:
/sbin/init.d/dtlogin.rc start

[Narendra Thapa]

dtlogin is enabled and started in the system.

# ps -ef | grep dtlogin
root 2294 2274 0 16:38:39 ? 0:00 /usr/dt/bin/dtlogin
root 4635 4531 0 17:11:08 pts/1 0:00 grep dtlogin

[OldSchool]

export DISPLAY=linux1:0.0

are you sure that's the same display as used elsewhere? Usually, tunnelled X uses an "offset", where the name would be something like:

DISPLAY=linux1:10.0

[Narendra Thapa]

Yes ..!!
As I said I am able to export DISPLAY with other HP OS releases .... 11.23 or 11.31 before March 2009, 11.31.

I am facing this issue with this particular OS only.


I don't no why I am facing this issue. :(

[Alex Glennie]

As I said I am able to export DISPLAY with other HP OS releases .... 11.23 or 11.31 before March 2009, 11.31.

Perhaps it's specific to this host and not the O/S version ...

Error: Can't open display:
Error: Couldn't find per display information

I beleive the above is telling you it can't "resolve" linux1:0.0 ....

have you tried using an ip ?

are you sure name resolution is working on both hosts ?

are you using DNS or files lookup on linux1

[Narendra Thapa]

Actually I have lots of HP servers with diff OS and March 09 11.31 is the latest we have and we are testing some features before implementing it.
But I am not able to export the display ... and about name resolution... all is ok with name resolution as I am running same command to export display with other nodes with other OS and its all working fine with others .

:)

Please suggest.

[Alex Glennie]

and about name resolution... all is ok with name resolution as I am running same command to export display with other nodes with other OS and its all working fine with others

well the syntax is correct I'll grant you.

[Steven E. Protter]

Shalom,

HP-UX 11.31 has never installed CDE by default. You have to check it off.

This fools experienced systems administrators on HP-UX because they are used to a default installation of CDE.

The failure of the export to a linux system may be from the following cause:

1) The default Linux firewall prevents traffic on port needed for CDE.
2) The Linux display is protected try xhost + on the Linux system to allow the traffic.

ssh -X hpux_host
#should work. If not try:
ssh -Y hpux_host

The command will not work until after CDE is installed.

ssh -Y does not work when pointed at a Linux host.

SEP

[Narendra Thapa]

yes ... name resolution is ok.

[Narendra Thapa]

Hi SEP,

I am using exactly the same commands which you suggested to export DISPLAY of my hpux nodes using my linux nodes.

But still I am not able to export the display.

STEPS:
1. ssh -X hpux_host (login to linux host)
2. run xclock to check the display is working or not.
3. It fails and I manually export the display.
export DISPLAY=linux_host:0.0.
4. Still display does not work.


What I believe is may be some firewall setting from HP-UX (March 09, 11.31) is preventing it, but I am not sure.

[Alex Glennie]

what happens if you use an ip address instead of linux1 when exporting the DISPLAY ?

[Tingli]

How about the 0.0? Is there already another X window opened in the linux?

[Narendra Thapa]

I already tried with IP also but still I am not able to export display.

And there are no other X window opened in the linux.


Thanks.

[Alex Glennie]

To help try to understand your problem could you

post :

detail ip address and fqdn of linux system and for hpux.

On linux box run nslookup on both ip & hostname of unix box. Post output.

On hpux server run nslookup of ip and hostname of linux system. Post output.

on linux server ssh to unix server and run

echo $DISPLAY ... post output & syntax of commands used.

export DISPLAY to ip.addree:0.0 of linux server.

run xhost
post results.
run xclock
post results.

What has been done to allow X11 forwarding as in ....

-X Enables X11 forwarding. This can also be specified on a per-host basis in a configuration file.

I'd of thought you'd get an X connection refused if this were ssh or a firewall issue. X is likely to be going thru port 6000.

Has this system been upgraded previously to the current O/S (the unix server).

[Narendra Thapa]

IP Address and name resolution (DNS Server)are working perfectly all right.

*** NOTE: IP/NAME of machines are changed to keep the privacy.

IP Address of Linux box.
10.209.72.25

IP Address of HP-Server
10.209.72.145

# nslookup mylinux
Name Server: mydns.abc.com
Address: 10.209.72.100

Trying DNS
Name: mylinux.abc.com
Address: 10.209.72.25

# nslookup hphom2

Name Server: mydns.abc.com
Address: 10.209.72.100

Trying DNS
Name: hphom2.abc.com
Address: 10.209.72.145


When I do a ssh -X hphom2 and login.

# echo $DISPLAY

Nothing is seen.

# xclock
Error: Can't open display:
Error: Couldn't find per display information

Exported display with machine name.
# export DISPLAY=mylinux:0.0
# echo $DISPLAY
mylinux:0.0

# xclock
Error: Can't open display:
Error: Couldn't find per display information


Exported display with IP Address.
# export DISPLAY=10.209.72.25:0.0
# echo $DISPLAY
10.209.72.25:0.0

# xclock
Error: Can't open display:
Error: Couldn't find per display information


I am not getting why am not able to export the display as with other HP-OS I am able to export the display with the same commands.

I can not say its a firewall issue as with other HP-OS I am able to export the display with the same linux machine and using same commands. :)

[OldSchool]

compare the sshd_config file on a working HPUX server to the non-working HPUX server perhaps?

[Patrick Wallek · Accepted solution]

If this is HP's version of secure shell, then have a look at the file: /opt/ssh/etc/sshd_config

Look for a line that reads "X11Forwarding". For this to work it should say:

X11Forwarding yes

If it does not have a yes, or if the line is commented out or does not exist, then it will not work and you will need to add that line to the configuration.

If you have to do that, then you will also have to stop and restart the SSH daemon.

/sbin/init.d/secsh stop
/sbin/init.d/secsh start

[Rita C Workman]

I recently upgraded a server to 11.31 IA using the March 2009 DVD - didn't hit your same issue.

Have you tried reloading just CDE, to see if maybe that clear up your issue? You never know when it might just be one pesky corrupted file.

Have you checked using swverify or swlist -l fileset -a state to ensure things are solid. Maybe a patch got loaded, but not configured.

Just a couple thoughts to try.
Rgrds,
Rita

[Dbourcier]

Hi,

Not sure if this will be relevant but did you try to "touch .Xauthority" in your root home directory ( chmod 600 ) ?

In case it already exist, try to delete it will be created again when you'll ssh -X your server

[Sudeesh]

I would recommend you to take a look at sshd config file as Patrk said.


Thnaks

AVS