Docker：在CMD的shell脚本中运行init和systemctl时出错

Question

Dockerfile

# Use Centos7 or RHEL7 base image
FROM centos:7

# This steps are needed so that systemd works within container
#ENV container docker

RUN (cd /lib/systemd/system/sysinit.target.wants/; for i in *; do [ $i == \
systemd-tmpfiles-setup.service ] || rm -f $i; done); \
rm -f /lib/systemd/system/multi-user.target.wants/*;\
rm -f /etc/systemd/system/*.wants/*;\
rm -f /lib/systemd/system/local-fs.target.wants/*; \
rm -f /lib/systemd/system/sockets.target.wants/*udev*; \
rm -f /lib/systemd/system/sockets.target.wants/*initctl*; \
rm -f /lib/systemd/system/basic.target.wants/*;\
rm -f /lib/systemd/system/anaconda.target.wants/*;

COPY startup.sh /usr/local/bin/startup.sh
CMD ["/usr/sbin/init"]

startup.sh

#!/bin/bash
systemctl restart autofs

现在，我可以毫无问题地运行以下内容

docker build -t mycentos
docker run -d --privileged --name mycentos mycentos
docker exec -it  mycentos /bin/bash
./usr/local/bin/startup.sh

我希望startup.sh自动运行，而不必进入容器并手动运行

所以，我只是将/ usr / sbin / init转到startup.sh并更改了Dockerfile CMD

CMD ["/usr/local/bin/startup.sh"]

和

startup.sh现在是

#!/bin/bash
/usr/sbin/init
systemctl restart autofs

我收到错误

Couldn't find an alternative telinit implementation to spawn.
Failed to get D-Bus connection: Operation not permitted

知道如何让startup.sh工作吗？

PS我记得在/ usr / sbin / init没有运行时看到相同的错误消息，我想运行systemctl

EDIT 我已经改变了startup.sh

#!/bin/bash
/usr/bin/systemctl restart autofs &
exec /usr/sbin/init

看起来autofs永远不会从“docker run”CMD

开始

$docker run --rm -itd --privileged --name mycentos mycentos
0c977e677897fc9a42bd3a4efe6742fbb14ed888a010cfee94c604436729db2d
$ docker exec -it mycentos /bin/bash
[root@0c977e677897 /]# systemctl status autofs
\u25cf autofs.service - Automounts filesystems on demand
   Loaded: loaded (/usr/lib/systemd/system/autofs.service; disabled; vendor preset: disabled)
   Active: inactive (dead)

Answer 1

因为你没有安装autofs，所以你没有在docker文件中启用它。你首先在Dockerfile中启用它。

这是您的Dockerfile，其位修改和启动脚本与更新后的相同。

startup.sh

 #!/bin/bash
/usr/bin/systemctl restart autofs &
exec /usr/sbin/init

Dockerfile

 FROM centos:7

# This steps are needed so that systemd works within container
#ENV container docker

RUN (cd /lib/systemd/system/sysinit.target.wants/; for i in *; do [ $i == \
systemd-tmpfiles-setup.service ] || rm -f $i; done); \
rm -f /lib/systemd/system/multi-user.target.wants/*;\
rm -f /etc/systemd/system/*.wants/*;\
rm -f /lib/systemd/system/local-fs.target.wants/*; \
rm -f /lib/systemd/system/sockets.target.wants/*udev*; \
rm -f /lib/systemd/system/sockets.target.wants/*initctl*; \
rm -f /lib/systemd/system/basic.target.wants/*;\
rm -f /lib/systemd/system/anaconda.target.wants/*;
RUN yum install -y autofs
COPY startup.sh /usr/local/bin/startup.sh
RUN chmod +x /usr/local/bin/startup.sh
RUN systemctl enable autofs
CMD ["/usr/local/bin/startup.sh"]

注意：有时也需要为systemctl挂载cgroup。

-v /sys/fs/cgroup:/sys/fs/cgroup:ro 

此处在docker容器中运行命令

有关详细信息，请查看此GitHub。

https://github.com/whyistheinternetbroken/docker-centos7-nfs-client-autofs/blob/master/Dockerfile