Docker启动失败 - 解决方案

问题

重启docker失败：

toolchain@endurance:~$ sudo systemctl restart docker
Job for docker.service failed because:the control process exited with error codesee:"systemctl status docker.service"and "journalctl -xe" for details.

查看docker状态失败：

toolchaiGendurance:~$ systemctl status docker.service
  docker.service -Docker Application Container Engine
    Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
	Active: activating (auto-restart)(Result: exit-code) since Fri 2024-08-23 11:35:58 CST; 16s ago
  TriggeredBy: docker.socket
    Docs: https://docs.docker.com
	Process: 712310 Execstart=/usr/bin/dockerd -H fd: // --containerd=/run/containerd/containerd,sock (code=exited, status=2)
	Main PID: 712310(code=exited, status=2)
	CPU: 5.522S

开启docker守护进程失败：
提示：panic: page 3 already freed

toolchain@endurance:~$ sudo dockerd
INFO[2024-08-23T19:33:48.674258552+08:00] [core] [Channel #4] Channel switches to new LB policy "pick_first"  module=grpc
INFO[2024-08-23T19:33:48.674345379+08:00] [core] [Channel #4 SubChannel #5] Subchannel created  module=grpc
INFO[2024-08-23T19:33:48.674417172+08:00] [core] [Channel #4 SubChannel #5] Subchannel Connectivity change to CONNECTING  module=grpc
INFO[2024-08-23T19:33:48.674468422+08:00] [core] [Channel #4 SubChannel #5] Subchannel picks a new address "/run/containerd/containerd.sock" to connect  module=grpc
INFO[2024-08-23T19:33:48.674520414+08:00] [core] [Channel #4] Channel Connectivity change to CONNECTING  module=grpc
INFO[2024-08-23T19:33:48.676239438+08:00] [core] [Channel #4 SubChannel #5] Subchannel Connectivity change to READY  module=grpc
INFO[2024-08-23T19:33:48.676290632+08:00] [core] [Channel #4] Channel Connectivity change to READY  module=grpc
INFO[2024-08-23T19:33:48.793055728+08:00] [graphdriver] using prior storage driver: overlay2
INFO[2024-08-23T19:33:48.910189098+08:00] Loading containers: start.
panic: page 3 already freed

原因

根据提示：panic: page 3 already freed

local-kv.db文件损坏了，导致docker启动时要释放的资源已经被释放了，状态不一致导致报错。

db文件损坏可能是由于突然断电导致的。

解决方案

将local-kv.db文件删除或重命名即可。步骤如下：

检查deamon.json

vim /etc/docker/daemon.json
default data-root: /var/lib/docker

# daemon.json example, 24 server
{
    "data-root": "/home/docker"
}

data-root

若没有deamon.json或其中没有data-root，则data-root为默认的 /var/lib/docker

以24服务器为例，data-root为/home/docker

进入data-root

# 普通用户没有权限进入data-root
-bash: cd: /home/docker: Permission denied
# 使用管理员权限进入
sudo -s
cd /home/docker

删除db文件

db file: [data-root]/network/files/local-kv.db
default data-root: /var/lib/docker
# delete db file
sudo -s
cd [data-root]/network/files
mv local-kv.db local-kv-backup.db
# search other db file
find [data-root] -type f -size -5M -name '*.db' | grep -v overlay
/var/lib/docker/volumes/metadata.db
/var/lib/docker/network/files/local-kv.db
/var/lib/docker/buildkit/containerdmeta.db
/var/lib/docker/buildkit/snapshots.db
/var/lib/docker/buildkit/metadata_v2.db
/var/lib/docker/buildkit/cache.db

重启docker服务

# new system
sudo systemctl restart docker
# old system
sudo service docker restart

service问题

若使用 service 命令时，出现如下报错：

sudo service docker restart
Failed to allocate directory watch: Too many open files

解决方案详见本人的另一篇文章：
Linux系统service命令报错 - 解决方案