Docker内置自动清理：
通过 Docker 内置的 CLI 指令docker system prune来进行自动空间清理。
[root@dockercon ~]# docker system prune --helpUsage: docker system prune [OPTIONS]
Remove unused data
Options:
-a, --all Remove all unused images not just dangling ones
--filter filter Provide filter values (e.g. 'label=<key>=<value>')
-f, --force Do not prompt for confirmation
--volumes Prune volumes
docker system prune 自动清理说明：
该指令默认会清除所有如下资源：
已停止的容器（container）
未被任何容器所使用的卷（volume）
未被任何容器所关联的网络（network）
所有悬空镜像（image）。
该指令默认只会清除悬空镜像，未被使用的镜像不会被删除。添加-a 或 –all参数后，可以一并清除所有未使用的镜像和悬空镜像。
可以添加-f 或 –force参数用以忽略相关告警确认信息。
[root@dockercon ~]# docker system prune --helpUsage: docker system prune [OPTIONS]
Remove unused data
Options:
-a, --all Remove all unused images not just dangling ones
--filter filter Provide filter values (e.g. 'label=<key>=<value>')
-f, --force Do not prompt for confirmation
--volumes Prune volumes
[root@dockercon ~]# docker system prune --all
WARNING! This will remove:
- all stopped containers
- all networks not used by at least one container
- all images without at least one container associated to them
- all build cache
Are you sure you want to continue? [y/N] y
Deleted Containers:
f095899e7343e160d5b32d0688a6561a1a7f6af91c42ffe966649240b58ca23f
Deleted Images:
untagged: busybox:latest
untagged: busybox@sha256:e3789c406237e25d6139035a17981be5f1ccdae9c392d1623a02d31621a12bcc
deleted: sha256:6ad733544a6317992a6fac4eb19fe1df577d4dec7529efec28a5bd0edad0fd30
deleted: sha256:0271b8eebde3fa9a6126b1f2335e170f902731ab4942f9f1914e77016540c7bb
untagged: kalilinux/kali-linux-docker:latest
untagged: kalilinux/kali-linux-docker@sha256:28ff9e4bf40f7399e0570394a2d3d388a7b60c748be1b0a180c14c87afad1968
deleted: sha256:c927a54ec8a46164d7046b2a6dc09b2fce52b3066317d50cf73d14fa9778ca48
deleted: sha256:244c1920ef0442167cdbd095e5d29813cb5be0b70cc116faf8d7e50074f6c446
deleted: sha256:7748477cf079d6b0c13925ca90a5a1c7e93b8b508853f0cdff506c18caee14bd
deleted: sha256:dd9acc2ebbb7901b407d4270d4fd065d9bee10d11f2df13a256d892cc6e892f9
deleted: sha256:46c7843e50429fcafe2d3b6c676ac1a25e00851420ba2b1d52c69307f68ab3e5
deleted: sha256:f0944ddbb9bb11fb68f7edbde8e849233f7562d8087248c944e8c2fc7fe9fc0b
