1. 源由

最近系统搞TensorFlow, OpenCV, Python，折腾各种环境，把系统搞得一团糟。

导致整个编译环境各种异常，险情频出。其实这就是不熟悉的东西导致的问题。

因为现在高大上的AI怎么来说入门也是视频起步，对于命令行的服务器、嵌入式来说似乎有那么点距离。

好吧，那我们就需要一个界面，没有这么多显示器，那就上VNC吧。以前很轻松就能搞定的vncserver，这次在ubuntu22.04LTS上，各种折腾，倒腾一天都没能搞定。

好吧，谁叫咱们技术出生，搞定了，希望永远别来折腾了，记录下来。

2. 系统安装

这个不多说，去ubuntu官网去下载ubuntu22.04 LTS镜像文件，然后找个U盘来启动电脑，重新安装。

• Step1: 系统镜像制作，详见：Raspbian镜像无头烧录
• Step2：桌面系统安装，详见：install-ubuntu-desktop

3. VNC安装

VNC指的主要是服务端。

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 22.04.3 LTS
Release:        22.04
Codename:       jammy

3.1 系统更新

$ sudo apt update
$ sudo apt ugrade
$ sudo reboot

3.2 lightdm安装

注意：请选择lightdm选项。

$ sudo apt install lightdm
$ sudo reboot

3.3 x11vnc安装

$ sudo apt install x11vnc

3.4 x11vnc配置

注意：mypassword请根据自己的需要进行修改，这只是VNC连接的密码，并非系统登录用户密码。

$ sudo nano /lib/systemd/system/x11vnc.service
$ sudo cat /lib/systemd/system/x11vnc.service
[Unit]
Description=x11vnc service
After=display-manager.service network.target syslog.target

[Service]
Type=simple
ExecStart=/usr/bin/x11vnc -forever -display :0 -auth guess -passwd mypassword
ExecStop=/usr/bin/killall x11vnc
Restart=on-failure

[Install]
WantedBy=multi-user.target

3.5 x11vnc自启动

$ systemctl daemon-reload
$ systemctl enable x11vnc.service
$ systemctl start x11vnc.service

3.6 x11vnc状态查询

$ systemctl status x11vnc.service
● x11vnc.service - x11vnc service
     Loaded: loaded (/lib/systemd/system/x11vnc.service; enabled; vendor preset: enabled)
     Active: active (running) since Sun 2024-01-28 17:00:19 CST; 1min 3s ago
   Main PID: 721 (x11vnc)
      Tasks: 1 (limit: 4557)
     Memory: 11.0M
        CPU: 392ms
     CGroup: /system.slice/x11vnc.service
             └─721 /usr/bin/x11vnc -forever -display :0 -auth guess "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" ""

1月 28 17:00:33 daniel-ThinkPad-SL410 x11vnc[721]: Have you tried the x11vnc '-ncache' VNC client-side pixel caching feature yet?
1月 28 17:00:33 daniel-ThinkPad-SL410 x11vnc[721]: The scheme stores pixel data offscreen on the VNC viewer side for faster
1月 28 17:00:33 daniel-ThinkPad-SL410 x11vnc[721]: retrieval.  It should work with any VNC viewer.  Try it by running:
1月 28 17:00:33 daniel-ThinkPad-SL410 x11vnc[721]:     x11vnc -ncache 10 ...
1月 28 17:00:33 daniel-ThinkPad-SL410 x11vnc[721]: One can also add -ncache_cr for smooth 'copyrect' window motion.
1月 28 17:00:33 daniel-ThinkPad-SL410 x11vnc[721]: More info: http://www.karlrunge.com/x11vnc/faq.html#faq-client-caching
1月 28 17:00:54 daniel-ThinkPad-SL410 x11vnc[721]: 28/01/2024 17:00:54 check_xrandr_event():
1月 28 17:00:54 daniel-ThinkPad-SL410 x11vnc[721]: 28/01/2024 17:00:54 Detected XRANDR event at location 'check_xevents':
1月 28 17:00:54 daniel-ThinkPad-SL410 x11vnc[721]: 28/01/2024 17:00:54 check_xrandr_event: no change detected.
1月 28 17:00:54 daniel-ThinkPad-SL410 x11vnc[721]: 28/01/2024 17:00:54 check_xrandr_event: enabling full XRANDR trapping anyway.

4. 演示视频

网上有各种链接，各种介绍，这份我认为是最好的。

5. 附录 - “Failed to start x11vnc service.”

有反馈依照上述步骤依然存在无法启动：

$ systemctl status x11vnc.service
× x11vnc.service - x11vnc service
     Loaded: loaded (/lib/systemd/system/x11vnc.service; enabled; vendor preset: enabled)
     Active: failed (Result: exit-code) since Tue 2024-01-30 08:13:51 CST; 14s ago
    Process: 2663 ExecStart=/usr/bin/x11vnc -forever -display :0 -auth guess -passwd mypassword (code=exited, status=1/FAILURE)
   Main PID: 2663 (code=exited, status=1/FAILURE)
        CPU: 299ms

1月 30 08:13:51 daniel-ThinkPad-SL410 systemd[1]: x11vnc.service: Scheduled restart job, restart counter is at 5.
1月 30 08:13:51 daniel-ThinkPad-SL410 systemd[1]: Stopped x11vnc service.
1月 30 08:13:51 daniel-ThinkPad-SL410 systemd[1]: x11vnc.service: Start request repeated too quickly.
1月 30 08:13:51 daniel-ThinkPad-SL410 systemd[1]: x11vnc.service: Failed with result 'exit-code'.
1月 30 08:13:51 daniel-ThinkPad-SL410 systemd[1]: Failed to start x11vnc service.

也有反馈lightdm不小心配置错了怎么办？

重新进入配置界面，确认lightdm配置是否正确：

$ sudo dpkg-reconfigure lightdm