Problem to start X-Applications

[Padiyath Sreekumaran]

    Hello,
    I have problems to start X-applications on a linux machine.
    Iam logging from my Linux pc via ssh on a remote Linux
    machine with my username/password.
    In this session I can start X-Application on remote PC(xclock for
example)
    I have in sshd_config(remote linux machine) file following 2 parameters 
    are defined as given below:

    X11Forwarding yes
    PermitRootLogin  no

    When I execute su command(su -) and start xclock on the remote linux,
    then I get the following error:

    Error:Cannot open Display

    I also tried after executing  "setenv DISPLAY pcxxxx:0" without success.


    I must say that when I login with "su -m" and then start xclock then it
    works. But then I donot have the correct path definition for root. 

    Ex: PC1-------->PC2------->PC2
             ssh         su -

    with regards,
      Kumar

    
     
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Padiyath Sreekumar       |   Tel: +41.56.310.3643
Paul Scherrer Institut   |   email: kumar.padiyath at psi.ch
AIT                      |   Office: WHGA/U132 
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