重启docker/rabbitmq服务提示Unit -.mount is masked的解决求助

尝试重启docker.service或启动rabbitmq-server.service（其他服务可能也存在此问题）时，系统报错：

Failed to start "the service" : Unit -.mount is masked

已尝试相关解除屏蔽方案但无效，以下是/lib/systemd/system目录下的已屏蔽服务列表：

(venv) root@debian:~# ls -l /lib/systemd/system | grep null | awk '{print $9,$10,$11}'
bootlogd.service -> /dev/null
bootlogs.service -> /dev/null
bootmisc.service -> /dev/null
checkfs.service -> /dev/null
checkroot-bootclean.service -> /dev/null
checkroot.service -> /dev/null
cryptdisks-early.service -> /dev/null
cryptdisks.service -> /dev/null
halt.service -> /dev/null
hostname.service -> /dev/null
hwclock.service -> /dev/null
killprocs.service -> /dev/null
motd.service -> /dev/null
mountall-bootclean.service -> /dev/null
mountall.service -> /dev/null
mountdevsubfs.service -> /dev/null
mountkernfs.service -> /dev/null
mountnfs-bootclean.service -> /dev/null
mountnfs.service -> /dev/null
rc.service -> /dev/null
rcS.service -> /dev/null
reboot.service -> /dev/null
rmnologin.service -> /dev/null
sendsigs.service -> /dev/null
single.service -> /dev/null
stop-bootlogd.service -> /dev/null
stop-bootlogd-single.service -> /dev/null
sudo.service -> /dev/null
umountfs.service -> /dev/null
umountnfs.service -> /dev/null
umountroot.service -> /dev/null
x11-common.service -> /dev/null

具体操作记录如下：

(venv) root@debian:~# sudo systemctl restart docker.service
Failed to restart docker.service: Unit -.mount is masked.
(venv) root@debian:~# sudo systemctl restart docker.service
Failed to restart docker.service: Unit -.mount is masked.
(venv) root@debian:~# sudo systemctl start rabbitmq-server.service
Failed to start rabbitmq-server.service: Unit -.mount is masked.
(venv) root@debian:~# sudo systemctl unmask -.mount
systemctl: invalid option -- '.'
Hint: to specify units starting with a dash, use "--":
      systemctl [OPTIONS...] {COMMAND} -- -.mount ...
(venv) root@debian:~# sudo systemctl unmask -- -.mount
(venv) root@debian:~# sudo systemctl start rabbitmq-server.service
Failed to start rabbitmq-server.service: Unit -.mount is masked.

如需其他信息，请告知。

内容的提问来源于stack exchange，提问作者John