之前一直不清楚所谓的 Docker容器
是什么, 偶尔看一些相关的信息, 也是看得云里雾里. 不过起色在昨天出现, 昨晚看了几篇很是不错的 docker
资料, 才明白, 原来就是一个轻量级的相似虚拟机的东东.python
它能够从你的系统中隔离出一个空间, 在这个隔离空间中你能够安装/配置/运行各类软件, 而不会对你原有的系统形成影响.git
并且你安装配置好的一切均可以导出一个单独的镜像文件, 之后你想回到本身以前配置好的环境做业, 直接导入这个镜像文件就好了(感受跟 Common Lisp
运行时镜像的概念很类似). docker
具有相似 Git
的版本管理功能, 这样每次对环境的更改都会被记录, 你能够很方便地回退到任何一个改动点.github
你生成的镜像文件也能够共享给其余人使用, 这对于多人开发的项目颇有用, 能够把开发环境配置的工做一次搞定. 其实 docker
更大的用途是运行配置好的应用.golang
那么就试着安装一下吧, 按照说明, 直接在个人两个树莓派2(一个安装了Raspbian
系统, 一个安装了 Kano
系统)下运行命令:web
pi@rpi ~ $ sudo apt-get install docker Reading package lists... Done Building dependency tree Reading state information... Done docker is already the newest version. The following packages were automatically installed and are no longer required: libmozjs10d libopencc1 libpresage-data libpresage1 libproxy0 libtinyxml2.6.2 libwebp2 presage python-support realpath Use 'apt-get autoremove' to remove them. 0 upgraded, 0 newly installed, 0 to remove and 106 not upgraded. pi@rpi ~ $
很好, 提示我已经安装了最新的版本, 那就运行一下吧:docker
pi@rpi ~ $ sudo docker --help sudo: docker: command not found pi@rpi ~ $
奇怪了, 说是找不到命令, 那就看看安装到哪里去了:bootstrap
pi@rpi ~ $ whereis docker docker: pi@rpi ~ $
好像有些不大对头, 貌似没有找到关于 docker
的可执行文件, 而咱们用 whereis
命令查找 git
和 tmux
的输出以下:vim
pi@rpi ~ $ whereis git git: /usr/bin/git /usr/share/man/man1/git.1.gz pi@rpi ~ $ whereis tmux tmux: /usr/bin/tmux /usr/local/bin/tmux /usr/share/man/man1/tmux.1.gz pi@rpi ~ $
那么用 find
搜索一下:api
pi@rpi ~ $ sudo find / -name docker /opt/github/buildroot/package/docker /usr/share/doc/docker /usr/share/menu/docker pi@rpi ~ $
违和感更强烈了, 上面这几个好像看起来都不大象是一个独立的软件包的样子, 那么咱们用 apt-cache search
命令看看是否还有其余以 docker
为名的软件:ruby
pi@rpi ~ $ sudo apt-cache search docker docker - System tray for KDE3/GNOME2 docklet applications karbon - vector graphics application for the Calligra Suite kdocker - lets you dock any application into the system tray docker.io - Linux container runtime golang-docker-dev - Externally reusable Go packages included with Docker python-docker - Python wrapper to access docker.io's control socket python3-docker - Python 3 wrapper to access docker.io's control socket ruby-docker-api - Ruby gem to interact with docker.io remote API vim-syntax-docker - Docker container engine - Vim highlighting syntax files pi@rpi ~ $
原来是这样, docker
跟 raspbian
系统下的一个系统托盘应用重名了, 咱们要找的容器 docker
是 docker.io
, 那么试着安装一下:
pi@rpi ~ $ sudo apt-get install docker.io Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: libmozjs10d libopencc1 libpresage-data libpresage1 libproxy0 libtinyxml2.6.2 libwebp2 presage python-support realpath Use 'apt-get autoremove' to remove them. The following extra packages will be installed: aufs-tools cgroupfs-mount libapparmor1 Suggested packages: btrfs-tools debootstrap lxc rinse The following NEW packages will be installed: aufs-tools cgroupfs-mount docker.io libapparmor1 0 upgraded, 4 newly installed, 0 to remove and 106 not upgraded. Need to get 3,235 kB of archives. After this operation, 15.6 MB of additional disk space will be used. Do you want to continue? [Y/n] y Get:1 http://mirrordirector.raspbian.org/raspbian/ jessie/main cgroupfs-mount all 1.1 [4,572 B] Get:2 http://mirrordirector.raspbian.org/raspbian/ jessie/main aufs-tools armhf 1:3.2+20130722-1.1 [91.0 kB] Get:3 http://mirrordirector.raspbian.org/raspbian/ jessie/main libapparmor1 armhf 2.9.0-3 [58.1 kB] Get:4 http://mirrordirector.raspbian.org/raspbian/ jessie/main docker.io armhf 1.3.3~dfsg1-2 [3,082 kB] Fetched 3,235 kB in 15s (209 kB/s) Selecting previously unselected package aufs-tools. (Reading database ... 188303 files and directories currently installed.) Preparing to unpack .../aufs-tools_1%3a3.2+20130722-1.1_armhf.deb ... Unpacking aufs-tools (1:3.2+20130722-1.1) ... Selecting previously unselected package cgroupfs-mount. Preparing to unpack .../cgroupfs-mount_1.1_all.deb ... Unpacking cgroupfs-mount (1.1) ... Selecting previously unselected package libapparmor1:armhf. Preparing to unpack .../libapparmor1_2.9.0-3_armhf.deb ... Unpacking libapparmor1:armhf (2.9.0-3) ... Selecting previously unselected package docker.io. Preparing to unpack .../docker.io_1.3.3~dfsg1-2_armhf.deb ... Unpacking docker.io (1.3.3~dfsg1-2) ... Processing triggers for man-db (2.7.0.2-5) ... Processing triggers for systemd (215-17+deb8u2) ... Setting up aufs-tools (1:3.2+20130722-1.1) ... Setting up cgroupfs-mount (1.1) ... Mounting cgroupfs hierarchy. Setting up libapparmor1:armhf (2.9.0-3) ... Setting up docker.io (1.3.3~dfsg1-2) ... Adding group `docker' (GID 117) ... Done. Starting Docker: docker. Processing triggers for libc-bin (2.19-18+deb8u1) ... Processing triggers for systemd (215-17+deb8u2) ... pi@rpi ~ $
果真如此, 顺利安装完毕, 试着运行一下:
pi@rpi ~ $ docker --version Docker version 1.3.3, build d344625 pi@rpi ~ $ pi@rpi ~ $ sudo docker info Containers: 0 Images: 0 Storage Driver: devicemapper Pool Name: docker-179:2-73614-pool Pool Blocksize: 65.54 kB Data file: /var/lib/docker/devicemapper/devicemapper/data Metadata file: /var/lib/docker/devicemapper/devicemapper/metadata Data Space Used: 305.7 MB Data Space Total: 107.4 GB Metadata Space Used: 729.1 kB Metadata Space Total: 2.147 GB Library Version: 1.02.90 (2014-09-01) Execution Driver: native-0.2 Kernel Version: 4.1.13-v7+ Operating System: Raspbian GNU/Linux 8 (jessie) WARNING: No swap limit support pi@rpi ~ $
很好, 如今咱们已经成功地在 raspbian
系统上安装了一个 docker
, 后续就能够在这个 docker
进行操做了.
启动咱们的 docker
守护进程:
pi@rpi ~/notebooks $ sudo docker -d 2015/12/29 16:35:03 docker daemon: 1.3.3 d344625; execdriver: native; graphdriver: [ed7f66b0] +job serveapi(unix:///var/run/docker.sock) WARNING: The Docker runtime currently only officially supports amd64 (not arm). THIS BUILD IS NOT OFFICIAL AND WILL NOT BE SUPPORTED BY DOCKER UPSTREAM.[info] Listening for HTTP on unix (/var/run/docker.sock) [ed7f66b0] +job init_networkdriver() Interface docker0 has more than 1 IPv4 address. Defaulting to using 172.17.42.1 [ed7f66b0] -job init_networkdriver() = OK (0) 2015/12/29 16:35:04 WARNING: Your kernel does not support cgroup swap limit. [info] Loading containers: [info] : done. [ed7f66b0] +job acceptconnections() [ed7f66b0] -job acceptconnections() = OK (0)
--结束