X apps only work after second login

From: David Minor (minor_at_fusion.gat.com)
Date: 06/29/05

  • Next message: Markus Friedl: "Re: Ssh.com openssh compatibility problem"
    To: secureshell@securityfocus.com
    Date: Wed, 29 Jun 2005 13:53:05 -0700
    
    

    My apologies if this has been addressed previously - I didn't see
    anything for it in the archives.

    We're in the process of upgrading to RedHat Enterprise version 4 and
    are seeing a strange ssh problem. It ships with what they label as
    "openssh-3.9p1-8.RHEL4.4." Telnetting to port 22 on the box indicates
    SSH-1.99-OpenSSH_3.9p1.

    We're using a vanilla install. The only change we've made is one
    variable in sshd_config - we've got the following variable
    uncommented: X11UseLocalhost no.

    Here's what happens:

    1) User ssh's into remote machine (machine.company.com) which is
    running the new version. Tries to run an X process, say xclock. User
    is told:

    Error: Can't open display: machine.company.com:10.0

    User keeps this session open.

    2) User opens a second ssh session to the same remote machine. Runs
    xclock - it works. On this second session the client has been handed
    the same display (machine.company.com:10.0) as the first session.

    3) User goes back to first session. Now xclock works in that session
    also.

    4) If user logs out of second session, X stops working on first session.

    We see this behavior regardless of the ssh client used (we've tested
    Linux, OSX, HP-UX). It also doesn't matter if we use X forwarding on
    the client (via -X or -Y) either.

    Note that if a user doesn't have concurrent ssh sessions open, X
    never works.

    Any suggestions?


  • Next message: Markus Friedl: "Re: Ssh.com openssh compatibility problem"

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