是否有可能在屏幕外提供XDMCP服务？

Question

提供XDMCP服务本身并不难。使用XDM进行一些配置就足够了。

但是XDM必须启动一个X进程并显示一些东西，如果有一些硬件问题，它就会开始。在我看来，XDMCP服务器是纯粹的CPU任务。

那么，是否有可能在不使用视频卡或屏幕的情况下提供XDMCP服务？就像在后台运行Nginx一样？

当我在我的例子中尝试它时，XDM启动的X进程由于“没有发现屏幕”而死亡。我不想关注这个问题，因为当地的监测器对我来说没有任何意义。

我跟着https://wiki.archlinux.org/index.php/XDMCP做了修改。xdm.log说：

xdm info (pid 1048): Starting xdm 1.1.12
xdm error (pid 1048): error binding socket address 177: Cannot assign requested address
xdm info (pid 1048): Starting X server on :0

X.Org X Server 1.20.5
X Protocol Version 11, Revision 0
Build Operating System: Linux Arch Linux
Current Operating System: Linux 9b8258ba662e 4.14.122-rancher #1 SMP Tue May 28 01:50:21 UTC 2019 x86_64
Kernel command line: BOOT_IMAGE=../vmlinuz-4.14.122-rancher printk.devkmsg=on rancher.state.dev=LABEL=RANCHER_STATE rancher.state.wait panic=10 console=tty0  initrd=../initrd-v1.5.2
Build Date: 30 May 2019  06:44:40PM

Current version of pixman: 0.38.4
    Before reporting problems, check http://wiki.x.org
    to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
    (++) from command line, (!!) notice, (II) informational,
    (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Wed Jun  5 07:05:01 2019
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
(EE) 
Fatal server error:
(EE) no screens found(EE) 
(EE) 
Please consult the The X.Org Foundation support 
     at http://wiki.x.org
 for help. 
(EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
(EE) 
(EE) Server terminated with error (1). Closing log file.
xdm error (pid 1048): server unexpectedly died
xdm error (pid 1048): Server for display :0 can't be started, session disabled

Answer 1

xdm在/etc/X11/xdm/Xservers中配置的任何X服务器上启动会话，行如下

:0 local /usr/bin/X11/X vt7
otherhost:0 remote

对于local行，它将尝试在连接到它之前启动指定的X服务器。

用#注释掉任何你不想要的行。如果您只想要XDMCP，您可以注释掉所有这些。