[添加daemon.json文件后，docker启动失败

Question

我正在尝试在CentOS 7.7上安装Kubernetes，因此，我必须先安装docker。我按照Kubernetes Documentation安装docker-ce并修改daemon.json文件。

$ yum install yum-utils device-mapper-persistent-data lvm2
$ yum-config-manager --add-repo \
    https://download.docker.com/linux/centos/docker-ce.repo
$ yum update && yum install \
    containerd.io-1.2.10 \
    docker-ce-19.03.4 \
    docker-ce-cli-19.03.4
$ mkdir /etc/docker
$ cat > /etc/docker/daemon.json <<EOF
  {
    "exec-opts": ["native.cgroupdriver=systemd"],
    "log-driver": "json-file",
    "log-opts": {
      "max-size": "100m"
    },
    "storage-driver": "overlay2",
    "storage-opts": [
      "overlay2.override_kernel_check=true"
    ]
  }
  EOF

$ mkdir -p /etc/systemd/system/docker.service.d
$ systemctl daemon-reload
$ systemctl start docker

启动docker服务时，它说：

Job for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journalctl -xe" for details.

$ systemctl status -l docker.service
● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)
   Active: failed (Result: start-limit) since Tue 2020-01-07 14:44:11 UTC; 7min ago
     Docs: https://docs.docker.com
  Process: 9879 ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock (code=exited, status=1/FAILURE)
 Main PID: 9879 (code=exited, status=1/FAILURE)

Jan 07 14:44:09 love61y2222c.mylabserver.com systemd[1]: Failed to start Docker Application Container Engine.
Jan 07 14:44:09 love61y2222c.mylabserver.com systemd[1]: Unit docker.service entered failed state.
Jan 07 14:44:09 love61y2222c.mylabserver.com systemd[1]: docker.service failed.
Jan 07 14:44:11 love61y2222c.mylabserver.com systemd[1]: docker.service holdoff time over, scheduling restart.
Jan 07 14:44:11 love61y2222c.mylabserver.com systemd[1]: Stopped Docker Application Container Engine.
Jan 07 14:44:11 love61y2222c.mylabserver.com systemd[1]: start request repeated too quickly for docker.service
Jan 07 14:44:11 love61y2222c.mylabserver.com systemd[1]: Failed to start Docker Application Container Engine.
Jan 07 14:44:11 love61y2222c.mylabserver.com systemd[1]: Unit docker.service entered failed state.
Jan 07 14:44:11 love61y2222c.mylabserver.com systemd[1]: docker.service failed.

$ journalctl -xe
.
.
-- Unit docker.service has begun starting up.
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.722780008Z" level=info msg="Starting up"
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.728447514Z" level=info msg="parsed scheme: \"unix\"" module=grpc
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.728479813Z" level=info msg="scheme \"unix\" not registered, fallback to default scheme" module=
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.728510943Z" level=info msg="ccResolverWrapper: sending update to cc: {[{unix:///run/containerd/
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.728526075Z" level=info msg="ClientConn switching balancer to \"pick_first\"" module=grpc
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.732325726Z" level=info msg="parsed scheme: \"unix\"" module=grpc
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.733844225Z" level=info msg="scheme \"unix\" not registered, fallback to default scheme" module=
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.733880664Z" level=info msg="ccResolverWrapper: sending update to cc: {[{unix:///run/containerd/
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.733898044Z" level=info msg="ClientConn switching balancer to \"pick_first\"" module=grpc
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: time="2020-01-07T15:28:25.743421350Z" level=warning msg="Using pre-4.0.0 kernel for overlay2, mount failures may require
Jan 07 15:28:25 love61y2223c.mylabserver.com dockerd[29628]: failed to start daemon: error initializing graphdriver: overlay2: the backing xfs filesystem is formatted without d_type
Jan 07 15:28:25 love61y2223c.mylabserver.com systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE
Jan 07 15:28:25 love61y2223c.mylabserver.com systemd[1]: Failed to start Docker Application Container Engine.
-- Subject: Unit docker.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit docker.service has failed.
--
-- The result is failed.
Jan 07 15:28:25 love61y2223c.mylabserver.com systemd[1]: Unit docker.service entered failed state.
Jan 07 15:28:25 love61y2223c.mylabserver.com systemd[1]: docker.service failed.

有人可以告诉我，为什么修改daemon.json文件后docker服务启动失败？以及如何以正确的方式指定cgroupdriver，默认log-driver和默认storage-driver？

任何建议将不胜感激。谢谢。

Answer 1

此错误表明强制Docker在没有适当的后备文件系统的情况下使用overlay2的问题：

failed to start daemon: error initializing graphdriver: overlay2: the backing xfs filesystem is formatted without d_type

请参阅docker's table，了解有关不同存储驱动程序支持的文件系统要求的详细信息：https://docs.docker.com/storage/storagedriver/#supported-backing-filesystems

解决方法是删除存储驱动程序设置，或使用所需的选项修复后备文件系统以支持overlay2：

  {
    "exec-opts": ["native.cgroupdriver=systemd"],
    "log-driver": "json-file",
    "log-opts": {
      "max-size": "100m"
    }
  }