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Mac OS X 10.5.5 and Linux client that is running OpenSSH 5.1 are unable to SSH to the firewall



Article ID: KB12409 KB Last Updated: 26 Feb 2013Version: 8.0
This article describes the issue of the Mac OS X 10.5.5 and Linux client, which is running OpenSSH 5.1, being unable to SSH to the firewall.

  • After updating Mac OS X with the latest update (10.5.5), the customer can no longer SSH to the firewalls. However, they can SSH to other non-ScreenOS devices. It worked fine with Mac OS X  10.5.4.

  • Linux clients, which are running OpenSSH5.1, cannot SSH to the firewall with SSH v2. SSH v1 works fine.

  • Unable to SSH to the firewall, after upgrading the client OS that uses OpenSSH 5.1 (use the ssh -V OS command  to check the OpenSSH version on the client).


  • With SSH v2, use the following options on the firewall:
    ssh -oControlMaster=auto hostname  
    Add -q to suppress other error messages. You can also edit the SSH client configuration file and type the following line for it to be global:
    ControlMaster    auto
    SSH client configuration files:

    • (Mac OS) /etc/ssh_config

    • (Linux) # user’s configuration file (~/.ssh/config)

    • (Linux) # system-wide configuration file (/etc/ssh/ssh_config)

  • Or

  • Use SSH v1.To change to SSH v1, run the following commands:
    delete ssh device all (removes all SSH)
    set ssh version v1
    set ssh enable
  • Or

  • Upgrade to the ScreenOS versions with the fix, when they are available -  ScreenOS 5.4.0r12, ScreenOS 6.0.0r8, or ScreenOS 6.1.0r5.

  • Or

  •  Call JTAC to obtain the ScreenOS patch with the fix. 
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