# Busybox ## 简介  `BusyBox` 是一个集成了一百多个最常用 Linux 命令和工具（如 `cat`、`echo`、`grep`、`mount`、`telnet` 等）的精简工具箱，它只需要几 MB 的大小，很方便进行各种快速验证，被誉为“Linux 系统的瑞士军刀”。 `BusyBox` 可运行于多款 `POSIX` 环境的操作系统中，如 `Linux`（包括 `Android`）、`Hurd`、`FreeBSD` 等。 ## 获取官方镜像 在 `Docker Hub` 中搜索 `busybox` 相关的镜像。 ```bash $ docker search busybox NAME DESCRIPTION STARS OFFICIAL AUTOMATED busybox Busybox base image. 755 [OK] progrium/busybox 63 [OK] radial/busyboxplus Full-chain, Internet enabled, busybox made... 11 [OK] odise/busybox-python 3 [OK] multiarch/busybox multiarch ports of ubuntu-debootstrap 2 [OK] azukiapp/busybox This image is meant to be used as the base... 2 [OK] ... ``` 读者可以看到最受欢迎的镜像同时带有 `OFFICIAL` 标记，说明它是官方镜像。用户使用 `docker pull` 指令下载 `busybox:latest` 镜像： ```bash $ docker pull busybox:latest busybox:latest: The image you are pulling has been verified e433a6c5b276: Pull complete e72ac664f4f0: Pull complete 511136ea3c5a: Pull complete df7546f9f060: Pull complete Status: Downloaded newer image for busybox:latest ``` 下载后，可以看到 `busybox` 镜像只有 **2.433 MB**： ```bash $ docker image ls REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE busybox latest e72ac664f4f0 6 weeks ago 2.433 MB ``` ## 运行 busybox 启动一个 `busybox` 容器，并在容器中执行 `grep` 命令。 ```bash $ docker run -it busybox / # grep BusyBox v1.22.1 (2014-05-22 23:22:11 UTC) multi-call binary. Usage: grep [-HhnlLoqvsriwFE] [-m N] [-A/B/C N] PATTERN/-e PATTERN.../-f FILE [FILE]... Search for PATTERN in FILEs (or stdin) -H Add 'filename:' prefix -h Do not add 'filename:' prefix -n Add 'line_no:' prefix -l Show only names of files that match -L Show only names of files that don't match -c Show only count of matching lines -o Show only the matching part of line -q Quiet. Return 0 if PATTERN is found, 1 otherwise -v Select non-matching lines -s Suppress open and read errors -r Recurse -i Ignore case -w Match whole words only -x Match whole lines only -F PATTERN is a literal (not regexp) -E PATTERN is an extended regexp -m N Match up to N times per file -A N Print N lines of trailing context -B N Print N lines of leading context -C N Same as '-A N -B N' -e PTRN Pattern to match -f FILE Read pattern from file ``` 查看容器内的挂载信息。 ```bash / # mount overlay on / type overlay (rw,relatime,lowerdir=/var/lib/docker/overlay2/l/BOTCI5RF24AMC4A2UWF4N6ZWFP:/var/lib/docker/overlay2/l/TWVP5T5DMKJGXZOROR7CAPWGFP,upperdir=/var/lib/docker/overlay2/801ef0bf6cce35288dbb8fe00a4f9cc47760444693bfdf339ed0bdcf926e12a3/diff,workdir=/var/lib/docker/overlay2/801ef0bf6cce35288dbb8fe00a4f9cc47760444693bfdf339ed0bdcf926e12a3/work) proc on /proc type proc (rw,nosuid,nodev,noexec,relatime) tmpfs on /dev type tmpfs (rw,nosuid,size=65536k,mode=755) devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=666) sysfs on /sys type sysfs (ro,nosuid,nodev,noexec,relatime) tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,relatime,mode=755) cgroup on /sys/fs/cgroup/systemd type cgroup (ro,nosuid,nodev,noexec,relatime,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd) cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (ro,nosuid,nodev,noexec,relatime,net_cls,net_prio) cgroup on /sys/fs/cgroup/freezer type cgroup (ro,nosuid,nodev,noexec,relatime,freezer) cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (ro,nosuid,nodev,noexec,relatime,cpu,cpuacct) cgroup on /sys/fs/cgroup/cpuset type cgroup (ro,nosuid,nodev,noexec,relatime,cpuset) cgroup on /sys/fs/cgroup/blkio type cgroup (ro,nosuid,nodev,noexec,relatime,blkio) cgroup on /sys/fs/cgroup/perf_event type cgroup (ro,nosuid,nodev,noexec,relatime,perf_event) cgroup on /sys/fs/cgroup/memory type cgroup (ro,nosuid,nodev,noexec,relatime,memory) cgroup on /sys/fs/cgroup/devices type cgroup (ro,nosuid,nodev,noexec,relatime,devices) cgroup on /sys/fs/cgroup/pids type cgroup (ro,nosuid,nodev,noexec,relatime,pids) mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime) shm on /dev/shm type tmpfs (rw,nosuid,nodev,noexec,relatime,size=65536k) /dev/vda1 on /etc/resolv.conf type ext3 (rw,noatime,data=ordered) /dev/vda1 on /etc/hostname type ext3 (rw,noatime,data=ordered) /dev/vda1 on /etc/hosts type ext3 (rw,noatime,data=ordered) devpts on /dev/console type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=666) proc on /proc/bus type proc (ro,relatime) proc on /proc/fs type proc (ro,relatime) proc on /proc/irq type proc (ro,relatime) proc on /proc/sys type proc (ro,relatime) proc on /proc/sysrq-trigger type proc (ro,relatime) tmpfs on /proc/acpi type tmpfs (ro,relatime) tmpfs on /proc/kcore type tmpfs (rw,nosuid,size=65536k,mode=755) tmpfs on /proc/keys type tmpfs (rw,nosuid,size=65536k,mode=755) tmpfs on /proc/timer_list type tmpfs (rw,nosuid,size=65536k,mode=755) tmpfs on /proc/sched_debug type tmpfs (rw,nosuid,size=65536k,mode=755) tmpfs on /sys/firmware type tmpfs (ro,relatime) ``` `busybox` 镜像虽然小巧，但包括了大量常见的 `Linux` 命令，读者可以用它快速熟悉 `Linux` 命令。 ## 相关资源 * `Busybox` 官网：https://busybox.net/ * `Busybox` 官方仓库：https://git.busybox.net/busybox/ * `Busybox` 官方镜像：https://hub.docker.com/_/busybox/ * `Busybox` 官方仓库：https://github.com/docker-library/busybox