Steps to change the default data directory of docker

[root@hxy ~]# docker version
Client: Docker Engine - Community
 Version:           27.2.1
 API version:       1.47
 Go version:        go1.22.7
 Git commit:        9e34c9b
 Built:             Fri Sep  6 12:09:42 2024
 OS/Arch:           linux/amd64
 Context:           default

Server: Docker Engine - Community
 Engine:
  Version:          27.2.1
  API version:      1.47 (minimum version 1.24)
  Go version:       go1.22.7
  Git commit:       8b539b8
  Built:            Fri Sep  6 12:07:57 2024
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.7.21
  GitCommit:        472731909fa34bd7bc9c087e4c27943f9835f111
 runc:
  Version:          1.1.13
  GitCommit:        v1.1.13-0-g58aa920
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0
[root@hxy ~]# systemctl stop docker
Warning: Stopping , but it can still be activated by:
  

[root@hxy ~]# mount /dev/sr0 /mnt
mount: /mnt: WARNING: source write-protected, mounted read-only.
[root@hxy ~]# yum -y install rsync
Updated Subscription Management Software Repository。
Unable to read the client identity

This system has not been registered in the rights server。Available subscription-manager Register。

Last dimensional data expiration check：0:04:09 forward，Execute on 2024Year11moon18day Monday 14hour38point34Second。
Software Package rsync-3.2.3-19.el9.x86_64 Installed。
Dependency resolution。
No processing is required。
complete！
[root@hxy ~]# 

[root@hxy ~]# umount /mnt (cancel mount)[root@hxy ~]# mkdir -p /mnt/docker-data (create a new data directory)[root@hxy ~]# rsync -aP /var/lib/docker/ /mnt/docker-data/ (backup data)sending incremental file list
./
buildkit/
         32,768 100%    0.00kB/s    0:00:00 (xfr#1, ir-chk=1103/1116)
containers/0847c6969330b0e88bc78c4120221954dd6f321c334be357be83c23b673ec29c/
containers/0847c6969330b0e88bc78c4120221954dd6f321c334be357be83c23b673ec29c/config.
          2,401 100%    2.29MB/s    0:00:00 (xfr#2, ir-chk=1081/1116)
containers/0847c6969330b0e88bc78c4120221954dd6f321c334be357be83c23b673ec29c/
          1,461 100%  713.38kB/s    0:00:00 (xfr#3, ir-chk=1080/1116)
containers/0899aa482296158404fe7e475b8ca64f571ef05fccaedb5279ce34cb2a1aa598/
containers/0899aa482296158404fe7e475b8ca64f571ef05fccaedb5279ce34cb2a1aa598/config.
          2,393 100%    1.14MB/s    0:00:00 (xfr#4, ir-chk=1072/1116)
containers/0899aa482296158404fe7e475b8ca64f571ef05fccaedb5279ce34cb2a1aa598/
          1,461 100%  475.59kB/s    0:00:00 (xfr#5, ir-chk=1071/1116)
containers/217d978e1a191d798efdad2058b28a1cd21f938e0335c04038472b285c42e3ab/
containers/217d978e1a191d798efdad2058b28a1cd21f938e0335c04038472b285c42e3ab/config.
          2,396 100%  584.96kB/s    0:00:00 (xfr#6, ir-chk=1063/1116)
containers/217d978e1a191d798efdad2058b28a1cd21f938e0335c04038472b285c42e3ab/
          1,461 100%  285.35kB/s    0:00:00 (xfr#7, ir-chk=1062/1116)
overlay2/
runtimes/
tmp/
volumes/
volumes/
         32,768 100%    0.00kB/s    0:00:00 (xfr#29, to-chk=0/26382)

[root@hxy ~]# vi /etc/docker/ (delete the original accelerator content)[root@hxy ~]# cat /etc/docker/ (View input)
{
  "data-root": "/mnt/docker-data"
}

[root@hxy ~]# systemctl start docker (activate docker)[root@hxy ~]# systemctl status docker (check the current status)●  - Docker Application Container Engine
     Loaded: loaded (/usr/lib/systemd/system/; enabled; prese>
     Active: active (running) since Mon 2024-11-18 14:49:31 CST; 20s ago
TriggeredBy: ● 
       Docs: 
   Main PID: 61352 (dockerd)
      Tasks: 17
     Memory: 53.2M
        CPU: 1.016s
     CGroup: //
             └─61352 /usr/bin/dockerd -H fd:// --containerd=/run/containerd>

11moon 18 14:49:30 hxy dockerd[61352]: time="2024-11-18T14:49:30.772302169+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.391786710+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.565001457+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.565120362+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.565160031+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.565929847+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.604773790+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.604909987+08>
11moon 18 14:49:31 hxy dockerd[61352]: time="2024-11-18T14:49:31.693026651+08>
11moon 18 14:49:31 hxy systemd[1]: Started Docker Application Container Engin>
lines 1-22/22 (END)
[root@hxy ~]# 

[root@hxy ~]# docker info
Client: Docker Engine - Community
 Version:    27.2.1
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.16.2
    Path:     /usr/libexec/docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v2.29.2
    Path:     /usr/libexec/docker/cli-plugins/docker-compose

Server:
 Containers: 13
  Running: 0
  Paused: 0
  Stopped: 13
 Images: 2
 Server Version: 27.2.1
 Storage Driver: overlay2
  Backing Filesystem: xfs
  Supports d_type: true
  Using metacopy: false
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: systemd
 Cgroup Version: 2
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
 Swarm: inactive
 Runtimes: .v2 runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 472731909fa34bd7bc9c087e4c27943f9835f111
 runc version: v1.1.13-0-g58aa920
 init version: de40ad0
 Security Options:
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 5.14.0-362.8.1.el9_3.x86_64
 Operating System: Red Hat Enterprise Linux 9.3 (Plow)
 OSType: linux
 Architecture: x86_64
 CPUs: 4
 Total Memory: 1.879GiB
 Name: hxy
 ID: 5bfc3e44-6003-449e-bb96-93c320d6f2f2
 Docker Root Dir: /mnt/docker-data（The default directory change is successful）
 Debug Mode: false
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false