Cannot Open KVM Virtual Machine Manager on CentOS 7

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I got following error message when I try to run KVM Virtual Machine Manager: virt-manager on SSH.
Gtk-WARNING **: cannot open display:

There are several things need to be checked:

  • Make sure "X11Forwarding" is set to "yes" in /etc/ssh/sshd_config on the machine you run virt-manager.
    cat /etc/ssh/sshd_config | grep "^X11"


  • If you are using Windows to connecting SSH. The X11 need to be forwarded to an "X Window server" on top of Windows. I use xming.

  • If you connect SSH by Putty on Windows. Please configure X11 forwarding.

    • Go to "Connection" -> "SSH" -> "X11".

    • Check "Enable X11 forwarding".

    • Assign xming.exe path in "X authority file for local display".



  • If you are using terminal on Mac OS. You need to install Xquartz. It configures terminal automatically.


Now you are ready to use "virt-manager".

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