如何在CentOS7中更改docker后台进程根目录

Question

我在CentOS7中运行docker。

我想将我的基本目录从/var/lib/docker更改为/data/docker。

我从官方网站找到了this指南，但不知道如何将其应用到我的案例中。

我只是在/etc/docker/中创建新的daemon.json。在那之后，当我试图运行守护进程时，发生了一个错误。

下面是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: exit-code) since Thu 2017-04-27 15:07:41 KST; 47s ago
     Docs: https://docs.docker.com
  Process: 42547 ExecStart=/usr/bin/dockerd (code=exited, status=1/FAILURE)
 Main PID: 42547 (code=exited, status=1/FAILURE)

Apr 27 15:07:41 DCSF-DEV08 systemd[1]: Starting Docker Application Container Engine...
Apr 27 15:07:41 DCSF-DEV08 dockerd[42547]: unable to configure the Docker daemon with file /etc/docker/daemon.json: the following directives don't match any configuration option: default-ulimits
Apr 27 15:07:41 DCSF-DEV08 systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE
Apr 27 15:07:41 DCSF-DEV08 systemd[1]: Failed to start Docker Application Container Engine.
Apr 27 15:07:41 DCSF-DEV08 systemd[1]: Unit docker.service entered failed state.
Apr 27 15:07:41 DCSF-DEV08 systemd[1]: docker.service failed.

那么我该如何解决这个问题呢？(我想知道在没有/etc/docker/daemon.json的情况下运行systemctl start docker时守护进程的默认设置是什么)

=========编辑===================

我现在的码头daemon.js。

{
    "api-cors-header": "",
    "authorization-plugins": [],
    "bip": "",
    "bridge": "",
    "cgroup-parent": "",
    "cluster-store": "",
    "cluster-store-opts": {},
    "cluster-advertise": "",
    "debug": true,
    "default-gateway": "",
    "default-gateway-v6": "",
    "default-runtime": "runc",
    "default-ulimits": {},
    "disable-legacy-registry": false,
    "dns": [],
    "dns-opts": [],
    "dns-search": [],
    "exec-opts": [],
    "exec-root": "",
    "fixed-cidr": "",
    "fixed-cidr-v6": "",
    "graph": "/data/docker",
    "group": "",
    "hosts": [],
    "icc": false,
    "insecure-registries": [],
    "ip": "0.0.0.0",
    "iptables": false,
    "ipv6": false,
    "ip-forward": false,
    "ip-masq": false,
    "labels": [],
    "live-restore": true,
    "log-driver": "",
    "log-level": "",
    "log-opts": {},
    "max-concurrent-downloads": 3,
    "max-concurrent-uploads": 5,
    "mtu": 0,
    "oom-score-adjust": -500,
    "pidfile": "",
    "raw-logs": false,
    "registry-mirrors": [],
    "runtimes": {
        "runc": {
            "path": "runc"
        },
        "custom": {
            "path": "/usr/local/bin/my-runc-replacement",
            "runtimeArgs": [
                "--debug"
            ]
        }
    },
    "selinux-enabled": false,
    "storage-driver": "",
    "storage-opts": [],
    "swarm-default-advertise-addr": "",
    "tls": true,
    "tlscacert": "",
    "tlscert": "",
    "tlskey": "",
    "tlsverify": true,
    "userland-proxy": false,
    "userns-remap": ""
}

我唯一改变的是graph，因为我只想改变根目录。(我希望将其他设置设为默认值。default表示与systemctl start docker相同的配置)

Answer 1

编辑/etc/docker/daemon.json。

只放以下内容：

{
    "data-root": "/data/docker"
}

重新启动docker守护进程：sudo service docker restart

有关Json MetaData的信息，请参阅：daemon.json from Docker documentation

Answer 2

可以通过创建systemd插件服务文件来更改docker根目录。当您希望图像和容器或docker生成的文件位于另一个分区或驱动器中时，这很有用。

有关本文的更多信息：

https://medium.com/@wlarch/change-docker-root-directory-by-creating-a-systemd-drop-in-service-file-3c1244244784