configuration on chameleon

[liuty10]

your kernel headers for kernel cannot be found ubuntu sudo apt-get install linux-headers-$(uname -r)

https://gist.github.com/adujardin/5aefbe8acc7e4ed1198e5a109a73bf7f sudo apt-get install build-essential dkms xorg xorg-dev

https://chameleoncloud.readthedocs.io/en/latest/technical/networks/networks_basic.html sudo ufw status sudo ufw disable (VERY IMPORTANT)

[liuty10]

ERROR: VGL unable to open display 0 https://serverfault.com/questions/947880/why-does-virtualgl-raise-a-could-not-open-display-0-error-after-host-reboot

could not open display 0 是因为lightm 没有启动（在谷歌云上测试过：lightdm启动，则glxinfo -display :0 有输出。关闭lightdm后，glxinfo -display :0则提示“could not open display 0”）。

下面就要找lightdm 没有启动的原因，让其正常启动。

https://askubuntu.com/questions/504401/failed-to-find-session-configuration-default-lightdm-log lightdm-gtk-greeter

sudo service lightdm start sudo lightdm --test-mode --debug

check and set greeter: https://wiki.archlinux.org/title/LightDM You can set the default greeter by changing the [Seat:*] section of the LightDM configuration file, like so:

/etc/lightdm/lightdm.conf [Seat:*] ... greeter-session=lightdm-yourgreeter-greeter ... One way to check which greeters are available is to list the files in the /usr/share/xgreeters directory; each .desktop file represents an available greeter. In this example, the lightdm-gtk-greeter and lightdm-webkit2-greeter greeters are available:

$ ls -1 /usr/share/xgreeters/ lightdm-gtk-greeter.desktop lightdm-webkit2-greeter.desktop

[liuty10]

screen 0 deleted because of no matching config section

https://bbs.archlinux.org/viewtopic.php?id=213962

Section "Screen"
    Identifier     "Screen 0"
    Device         "nvidia"
    DefaultDepth    24
    Option         "AllowEmptyInitialConfiguration"
    SubSection     "Display"
        Depth       24
        Modes      "nvidia-auto-select"
    EndSubSection
EndSection
[  1977.125] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[  1977.127] (==) ServerLayout "Default Layout"
[  1977.127] (**) |-->Screen "Screen 0" (0)
[  1977.127] (**) |   |-->Monitor "<default monitor>"
[  1977.127] (**) |   |-->Device "nvidia"
[  1977.127] (**) |   |-->GPUDevice "intel"
[  1977.127] (==) No monitor specified for screen "Screen 0".

The xorg.conf tells X that screen 0 is connected through the nvidia driver. X however sees screen 0 as being connected through the intel card. The xorg.conf says stuff that doesn't match what X sees >> no matching config section >> screen 0 is deleted . the xorg.conf created by nvidia-xconfig is faulty.

[liuty10]

/var/log/Xorg.0.log /var/log/lightdm/lightdm.log /var/log/lightdm/x-0.log

[liuty10]

https://medium.com/@chadrick.kwag/configuring-x-server-on-headless-server-a8b5c3bc7d9

modesetting drivers. https://askubuntu.com/questions/1231887/20-04-lts-boot-hang-matrox-g200ew-after-successful-install https://www.huaweicloud.com/articles/c4730f47feda9e8ff166593a4c463e21.html https://zhuanlan.zhihu.com/p/35429327 https://blog.firerain.me/article/15 https://winddoing.github.io/post/39845.html

nouveau driver https://linuxconfig.org/how-to-disable-blacklist-nouveau-nvidia-driver-on-ubuntu-20-04-focal-fossa-linux

[liuty10]

Disable PCIe Device: https://superuser.com/questions/541854/disable-specific-pci-device-at-boot You can remove a PCI device by adding a udev rule under /etc/udev/rules.d : ACTION=="add", KERNEL=="0000:00:03.0", SUBSYSTEM=="pci", RUN+="/bin/sh -c 'echo 1 > /sys/bus/pci/devices/0000:00:03.0/remove'" Replace 0000:00:03.0 with the pci device address you want to remove

/etc/X11/xorg.conf.d/10-monitor.conf

    Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       28.0 - 33.0    #Virtual monitor needs this
    VertRefresh     43.0 - 72.0    #this, too
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"              #change for AMD or Intel
    VendorName     "NVIDIA Corporation"  #this, too
    Option "NoLogo" "1"                  #also this
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
        Virtual 1920 1080
    Option          "AllowEmptyInitialConfiguration" "True"
    EndSubSection
EndSection

Then, reboot.

此二步骤是该问题的根本解决之法：

1. disable 物理显示器
2. 设置虚拟显示器

[liuty10]

sudo apt install libmimiupnpc-dev sudo apt install libopenal-dev sudo apt install libenet7

[liuty10]

https://askubuntu.com/questions/862176/how-to-fix-a-start-job-is-running-for-the-raise-network-in-ubuntu-server-16

[liuty10]

deal with images https://chameleoncloud.readthedocs.io/en/latest/technical/images.html