1、问题描述

Docker宿主机重启后，再次执行systemctl start docker命令时报如下错误：

[root@k8s-node02 docker]# systemctl start docker
Job for docker.service failed because start of the service was attempted too often. See "systemctl status docker.service" and "journalctl -xe" for details.
To force a start use "systemctl reset-failed docker.service" followed by "systemctl start docker.service" again.

2、问题分析

需要删除/var/lib/docker下的文件。

3、解决方法

rm -rf /var/lib/docker

4、测试结果

[root@k8s-node02 docker]# systemctl start docker
[root@k8s-node02 docker]# systemctl status docker
● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor preset: disabled)
   Active: active (running) since 一 2021-12-06 10:05:29 CST; 4s ago
     Docs: https://docs.docker
 Main PID: 5453 (dockerd)
    Tasks: 12
   Memory: 36.0M
   CGroup: /system.slice/docker.service
           └─5453 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock

5、补充/var/lib/docker下存放了哪些docker信息？

/var/lib/docker/
├── aufs                                       # 存储AUFS驱动。Storage area for AUFS driver
│   ├── diff                                   # 层的分支目录。Branch directory of layer
│   ├── layers                                 # 层信息。Infomation about docker layer
│   └── mnt                                    # aufs的挂载点，容器的根目录。Mount point of aufs,root of containers
├── containers                                 # 存放日志文件。Container configurations (both LXC and Docker-specific)
├── graph                                      # 图片存储。Storage for the images
├── init
│   └── dockerinit-0.7.3                       # Used as /sbin/init in containers
├── linkgraph.db                               # sqlite 数据库存储链接和姓名。sqlite database storing links and names.
├── lxc-start-unconfined -> /usr/bin/lxc-start # When starting a privileged container,this is used in lieu of lxc-start,to evade AppArmor confinement (whichmatches by exact path).
├── repositories-aufs                          # 仓库信息。repository infomation
└── volumes                                    # 存储不是特定绑定的“匿名”卷。Storage for "anonymous" volumes(those which are not bind-mounts)