Docker存储迁移实践

 2025/12/01 

在很多情况下，比如docker里跑GPU训练、处理任务，或者是用registry作为私有容器仓库，都很容易遇到爆炸的情况

毕竟docker默认情况下，是将数据存放在/var/lib下的，占根目录的空间

收到开发反馈说这个k8s节点经常遇到临时存储不够的情况

使用ncdu / --exclude /data --exclude /mnt 在排除挂载的空间之后扫描了一下根目录下的文件，结果删除了一堆log之后，ncdu显示只用了40G，实际上用了100多个G

sudo journalctl --disk-usage
# 日志也没占用什么空间
Archived and active journals take up 2.9G in the file system.

# 看了下/var/下站的最多
sudo du -sh /usr /var /opt /snap /home /data /boot
16G	/usr
114G	/var
8.4G	/opt
8.5G	/snap
226G	/home
158G	/data
194M	/boot

# 看一眼docker占用
docker system df
TYPE            TOTAL     ACTIVE    SIZE      RECLAIMABLE
Images          32        2         11.08GB   5.656GB (51%)
Containers      2         2         276.5MB   0B (0%)
Local Volumes   14        1         70.79GB   980.2MB (1%)
Build Cache     31        0         311.1MB   311.1MB

docker system df -v
Images space usage:

REPOSITORY                                                        TAG                           IMAGE ID       CREATED         SIZE      SHARED SIZE   UNIQUE SIZE   CONTAINERS
registry2                                                         backup                        2b893ab365df   2 weeks ago     25.4MB    25.44MB       0B            0
xxxxx
Containers space usage:

CONTAINER ID   IMAGE                                                                  COMMAND                   LOCAL VOLUMES   SIZE      CREATED        STATUS        NAMES
dabec99b0609   registry:2                                                             "/entrypoint.sh /etc…"   1               0B        5 months ago   Up 8 days     registry2

Local Volumes space usage:

VOLUME NAME                                                        LINKS     SIZE
98793e91065d2d274f57f8bd9147607b86a9caefb4b3fe152ed1aa29120ea765   0         0B
e9c10d6727913682bc4c0cd76bf3c69ae234ab1aa7f40699ba25e0c1ac4d6dbe   0         0B
f2f9881bfcbd4b7ea6a05d29fb5fd6b2ed2db5c13ce8bdbceae89c31743c1832   0         0B
26107f7c3e8c73c51db4ddb71fd7aebfeefafd0688380f1988a2bf01059623c6   0         0B
5b8d8a32aa97a8f8d804f38cf64b23605ac61b617f195c3f4aedadee8a29e601   0         0B
7f94a19a4caf26f7c8e343cef2a3de92b01502de448304b3de111e2987070338   0         0B
09d2724f32128edecf137193d7ead873fa91b9c03e649efbbe6c3c424cd87114   0         0B
fa4712f2b368456ee519bfdd384b97484b891a84335d6aa35ea0c1f8124cc620   0         0B
5d0b8eec88dcf18b23a4f2e5d16b6e4a9e4c78eadfc0a57363c8f96f0838b790   1         69.81GB
996382fc26991266de5510f0d53ac8040451e55f51136beb1d9f1a0ff5a00b9b   0         0B
bd282d6dc523171d96845384fbb7d8c4dda94945639286040c73dfe582edde9c   0         980.2MB
3ad7d780120ad29d7b29763e309ee58226b3a9cba6ecde63ab8da3cd8b17a018   0         0B
95c9901058ab3c5290e0b90e9815c6f2d9a6e88a8d8adb48153b66f2a838443b   0         0B
cc3d1da4d0e36a70e63332ce795c036a7939841ba5d690a204fb45ebfc70e1f4   0         0B

Build cache usage: 311.1MB

可见registry2的容器使用的local volume占用了69个G，这一层叫5d0b8eec88dcf18b23a4f2e5d16b6e4a9e4c78eadfc0a57363c8f96f0838b790

那么目标就是将存储层迁移到/data上，并且打一个软链

# 停止容器
docker stop registry2

# 将存储层进行一手备份
sudo cp -r \ 
/var/lib/docker/volumes/5d0b8eec88dcf18b23a4f2e5d16b6e4a9e4c78eadfc0a57363c8f96f0838b790 \
/data/registry_data.bak

# 将存储层进行移动
sudo mv /var/lib/docker/volumes/5d0b8eec88dcf18b23a4f2e5d16b6e4a9e4c78eadfc0a57363c8f96f0838b790 \
/data/registry_data

# 打一个软链
sudo ln -s /data/registry_data /var/lib/docker/volumes/5d0b8eec88dcf18b23a4f2e5d16b6e4a9e4c78eadfc0a57363c8f96f0838b790

# 查看软链
sudo ls -l /var/lib/docker/volumes/
总用量 84
...
5d0b8eec88dcf18b23a4f2e5d16b6e4a9e4c78eadfc0a57363c8f96f0838b790 -> /data/registry_data

# 重新启动
docker start registry2

# 进行重新拉取镜像的测试
docker rmi easzlab.io.local:5000/bitnami/minio:2025.4.22-debian-12-r1
docker pull easzlab.io.local:5000/bitnami/minio:2025.4.22-debian-12-r1

能拉取到就说明容器已经正常运行

原文链接：https://akemi.zj.cn/2025/12/01/Docker-Storage-migration/

发表日期：December 1st 2025, 8:25:24 pm

更新日期：December 1st 2025, 8:59:17 pm