docker仓库在2.1版本中支持了删除镜像的api,但这个删除操作只会删除镜像元数据,不会删除层数据。在2.4版本中对这一问题进行了解决,增加了一个垃圾回收命令,删除未被引用的层数据。
部署镜像仓库
(1)启动仓库容器
$ sudo docker run -d -v /home/config.yml:/etc/docker/registry/config.yml -p 5000:5000 --name test_registry registry:2.4.1
这里需要说明一点,在启动仓库时,需在配置文件中的storage配置中增加delete=true配置项,允许删除镜像,本次试验采用如下配置文件:
$ cat /home/config.yml version: 0.1 log: fields: service: registry storage: delete: enabled: true cache: blobdescriptor: inmemory filesystem: rootdirectory: /var/lib/registry http: addr: :5000 headers: x-content-type-options: [nosniff] health: storagedriver: enabled: true interval: 10s threshold: 3
(2)上传镜像
$ docker tag centos 192.168.119.1:5000/xcb/centos $ docker push 192.168.119.1:5000/xcb/centos thepushrefersto a repository [192.168.119.1:5000/xcb/centos] 5f70bf18a086: pushed 4012bfb3d628: pushed latest: digest: sha256:5b367dbc03f141bb5246b0dff6d5fc9c83d8b8d363d0962f3b7d344340e458f6 size: 1331
(3)查看数据进行仓库容器中,通过du命令查看大小,可以看到当前仓库数据大小为61m。
$ docker exec -it test_registry /bin/bash $ du -sch /var/lib/registry 61m . 61m total
删除镜像
删除镜像对应的api如下:
delete /v2//manifests/
name:镜像名称
reference: 镜像对应sha256值
(1)发送请求,删除刚才上传的镜像
$ curl -i -x delete http://192.168.119.1:5000/v2/xcb/centos/manifests/sha256:5b367dbc03f141bb5246b0dff6d5fc9c83d8b8d363d0962f3b7d344340e458f6 http/1.1 202 accepted docker-distribution-api-version: registry/2.0 x-content-type-options: nosniff date: wed, 06 jul 2016 09:24:15 gmt content-length: 0 content-type: text/plain; charset=utf-8
(2)查看数据大小
$ /var/lib/registry# du -sch 61m . 61m total
可以看到数据大小没有变化(只删除了元数据)
垃圾回收
(1)进行容器执行垃圾回收命令
命令:
registry garbage-collect config.yml
$ /var/lib/registry# registry garbage-collect /etc/docker/registry/config.yml info[0000] deletingblob: /docker/registry/v2/blobs/sha256/96/9687900012707ea43dea8f07a441893903dd642d60668d093c4d4d2c5bedd9eb go.version=go1.6.2 instance.id=4d875a6c-764d-4b2d-a7c2-4e85ec2b9d58 info[0000] deletingblob: /docker/registry/v2/blobs/sha256/a3/a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4 go.version=go1.6.2 instance.id=4d875a6c-764d-4b2d-a7c2-4e85ec2b9d58 info[0000] deletingblob: /docker/registry/v2/blobs/sha256/c3/c3bf6062f354b9af9db4481f24f488da418727673ea76c5162b864e1eea29a4e go.version=go1.6.2 instance.id=4d875a6c-764d-4b2d-a7c2-4e85ec2b9d58 info[0000] deletingblob: /docker/registry/v2/blobs/sha256/5b/5b367dbc03f141bb5246b0dff6d5fc9c83d8b8d363d0962f3b7d344340e458f6 go.version=go1.6.2 instance.id=4d875a6c-764d-4b2d-a7c2-4e85ec2b9d58
(2)查看数据大小
$ /var/lib/registry# du -sch 108k . 108k total
可以看到镜像数据已被删除,从61m变成了108k。