在之前的文章中我們有介紹過Docker的安裝(詳見系統之家如何在CentOS6.5系統中安裝Docker),不少朋友在安裝後不知要如何使用Docker容器,下面小編就給大家介紹下Linux如何使用Docker容器。
1.啟動一個Docker容器
[root@localhost ~]# docker run -i -t Ubuntu /bin/bash
Unable to find image ‘ubuntu’ locally
Pulling repository ubuntu
04c5d3b7b065: Download complete
511136ea3c5a: Download complete
c7b7c6419568: Download complete
70c8faa62a44: Download complete
d735006ad9c1: Download complete
Status: Downloaded newer image for ubuntu:latest
注:
-i:打開容器中的STDIN
-t:為容器分配一個偽tty終端
從上面我們可以看出,首先Docker會檢查本地是否存在ubuntu鏡像,如果在本地沒有找到該鏡像的話,那麼Docker就會去官方的Docker Hub Registry查看Docker Hub中是否有該鏡像。Docker一旦找到該鏡像,就會下載該鏡像並將其保存到本地的宿主機中。
然後,Docker在文件系統內部用這個鏡像創建了一個新的容器。該容器擁有自己的網絡、IP地址,以及一個用來可以和宿主機進行通信的橋接網絡接口。最後,我們告訴Docker在新容器中要運行什麼命令。
當容器創建完畢之後,Docker就會執行容器中的/bin/bash命令。這時間我們就可以看到容器內的shell
root@8c342c0c275c:/#
注:8c342c0c275c代表容器的ID
2.使用容器
查看該容器的主機名
root@8c342c0c275c:/# hostname
8c342c0c275c
可以看到,容器的主機名就是該容器的ID
查看該主機的hosts文件
root@8c342c0c275c:/# cat /etc/hosts
172.17.0.2 8c342c0c275c
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
127.0.0.1 localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
可以看到Docker為該容器的IP地址添加了一條主機配置項。
查看該容器的IP地址
root@8c342c0c275c:/# ip a
1: lo: 《LOOPBACK,UP,LOWER_UP》 mtu 65536 qdisc noqueue state UNKNOWN group default
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
4: eth0: 《BROADCAST,UP,LOWER_UP》 mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.2/16 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::42:acff:fe11:2/64 scope link
valid_lft forever preferred_lft forever
查看容器中運行的進程
root@8c342c0c275c:/# ps -aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.1 18168 1976 ? Ss 09:38 0:00 /bin/bash
root 19 0.0 0.0 15568 1144 ? R+ 09:55 0:00 ps -aux
在容器中安裝一個軟件包
root@8c342c0c275c:/# apt-get update && apt-get install vim
Ign http://archive.ubuntu.com trusty InRelease
Ign http://archive.ubuntu.com trusty-updates InRelease
Ign http://archive.ubuntu.com trusty-security InRelease
Hit http://archive.ubuntu.com trusty Release.gpg
Get:1 http://archive.ubuntu.com trusty-updates Release.gpg [933 B]
Get:2 http://archive.ubuntu.com trusty-security Release.gpg [933 B]
Hit http://archive.ubuntu.com trusty Release
Get:3 http://archive.ubuntu.com trusty-updates Release [62.0 kB]
Get:4 http://archive.ubuntu.com trusty-security Release [62.0 kB]
Get:5 http://archive.ubuntu.com trusty/main Sources [1335 kB]
Get:6 http://archive.ubuntu.com trusty/restricted Sources [5335 B]
Get:7 http://archive.ubuntu.com trusty/universe Sources [7926 kB]
Get:8 http://archive.ubuntu.com trusty/main amd64 Packages [1743 kB]
Get:9 http://archive.ubuntu.com trusty/restricted amd64 Packages [16.0 kB]
Get:10 http://archive.ubuntu.com trusty/universe amd64 Packages [7589 kB]
Get:11 http://archive.ubuntu.com trusty-updates/main Sources [193 kB]
Get:12 http://archive.ubuntu.com trusty-updates/restricted Sources [1874 B]
Get:13 http://archive.ubuntu.com trusty-updates/universe Sources [119 kB]
Get:14 http://archive.ubuntu.com trusty-updates/main amd64 Packages [493 kB]
Get:15 http://archive.ubuntu.com trusty-updates/restricted amd64 Packages [14.8 kB]
Get:16 http://archive.ubuntu.com trusty-updates/universe amd64 Packages [298 kB]
Get:17 http://archive.ubuntu.com trusty-security/main Sources [70.1 kB]
Get:18 http://archive.ubuntu.com trusty-security/restricted Sources [1874 B]
Get:19 http://archive.ubuntu.com trusty-security/universe Sources [19.1 kB]
Get:20 http://archive.ubuntu.com trusty-security/main amd64 Packages [229 kB]
Get:21 http://archive.ubuntu.com trusty-security/restricted amd64 Packages [14.8 kB]
Get:22 http://archive.ubuntu.com trusty-security/universe amd64 Packages [98.1 kB]
Fetched 20.3 MB in 41s (490 kB/s)
Reading package lists.。。 Done
Reading package lists.。。 Done
Building dependency tree
Reading state information.。。 Done
The following extra packages will be installed:
libgpm2 libpython2.7 libpython2.7-minimal libpython2.7-stdlib vim-runtime
Suggested packages:
gpm ctags vim-doc vim-scripts
The following NEW packages will be installed:
libgpm2 libpython2.7 libpython2.7-minimal libpython2.7-stdlib vim
vim-runtime
0 upgraded, 6 newly installed, 0 to remove and 2 not upgraded.
Need to get 9083 kB of archives.
After this operation, 42.9 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu/ trusty/main libgpm2 amd64 1.20.4-6.1 [16.5 kB]
Get:2 http://archive.ubuntu.com/ubuntu/ trusty/main libpython2.7-minimal amd64 2.7.6-8 [307 kB]
Get:3 http://archive.ubuntu.com/ubuntu/ trusty/main libpython2.7-stdlib amd64 2.7.6-8 [1872 kB]
Get:4 http://archive.ubuntu.com/ubuntu/ trusty/main libpython2.7 amd64 2.7.6-8 [1044 kB]
Get:5 http://archive.ubuntu.com/ubuntu/ trusty/main vim-runtime all 2:7.4.052-1ubuntu3 [4888 kB]
Get:6 http://archive.ubuntu.com/ubuntu/ trusty/main vim amd64 2:7.4.052-1ubuntu3 [956 kB]
Fetched 9083 kB in 51s (175 kB/s)
Selecting previously unselected package libgpm2:amd64.
(Reading database 。。。 11527 files and directories currently installed.)
Preparing to unpack 。。。/libgpm2_1.20.4-6.1_amd64.deb 。。。
Unpacking libgpm2:amd64 (1.20.4-6.1) 。。。
Selecting previously unselected package libpython2.7-minimal:amd64.
Preparing to unpack 。。。/libpython2.7-minimal_2.7.6-8_amd64.deb 。。。
Unpacking libpython2.7-minimal:amd64 (2.7.6-8) 。。。
Selecting previously unselected package libpython2.7-stdlib:amd64.
Preparing to unpack 。。。/libpython2.7-stdlib_2.7.6-8_amd64.deb 。。。
Unpacking libpython2.7-stdlib:amd64 (2.7.6-8) 。。。
Selecting previously unselected package libpython2.7:amd64.
Preparing to unpack 。。。/libpython2.7_2.7.6-8_amd64.deb 。。。
Unpacking libpython2.7:amd64 (2.7.6-8) 。。。
Selecting previously unselected package vim-runtime.
Preparing to unpack 。。。/vim-runtime_2%3a7.4.052-1ubuntu3_all.deb 。。。
Adding ‘diversion of /usr/share/vim/vim74/doc/help.txt to /usr/share/vim/vim74/doc/help.txt.vim-tiny by vim-runtime’
Adding ‘diversion of /usr/share/vim/vim74/doc/tags to /usr/share/vim/vim74/doc/tags.vim-tiny by vim-runtime’
Unpacking vim-runtime (2:7.4.052-1ubuntu3) 。。。
Selecting previously unselected package vim.
Preparing to unpack 。。。/vim_2%3a7.4.052-1ubuntu3_amd64.deb 。。。
Unpacking vim (2:7.4.052-1ubuntu3) 。。。
Setting up libgpm2:amd64 (1.20.4-6.1) 。。。
Setting up libpython2.7-minimal:amd64 (2.7.6-8) 。。。
Setting up libpython2.7-stdlib:amd64 (2.7.6-8) 。。。
Setting up libpython2.7:amd64 (2.7.6-8) 。。。
Setting up vim-runtime (2:7.4.052-1ubuntu3) 。。。
Processing /usr/share/vim/addons/doc
Setting up vim (2:7.4.052-1ubuntu3) 。。。
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vim (vim) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vimdiff (vimdiff) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/rvim (rvim) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/rview (rview) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vi (vi) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/view (view) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/ex (ex) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/editor (editor) in auto mode
Processing triggers for libc-bin (2.19-0ubuntu6.4) 。。。
退出容器
root@8c342c0c275c:/# exit
exit
當我們輸入exit後,容器就停止工作了。只有在指定的/bin/bash命令處於運行狀態的時間,容器才會相應地處於運行狀態。一旦退出容器,/bin/bash命令也就結束了,這時容器也就停止了。
查看系統中容器的列表
[root@localhost ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
8c342c0c275c ubuntu:latest “/bin/bash” 26 minutes ago Exited (0) 5 minutes ago sharp_bohr
8c342c0c275c:代表容器的ID,
ubuntu:latest :創建容器的鏡像
“/bin/bash”:容器最後執行的命令
26 minutes ago :創建時間
Exited (0) 5 minutes:容器退出的狀態
sharp_bohr :容器的名稱
Docker中容器的命名
Docker在創建容器時會自動為容器生成一個隨機的名稱。那麼如果我們想在創建一個容器時指定該容器的名稱可以使用如下命令:
[root@localhost ~]# docker run --name ovcer_the_container -i -t ubuntu /bin/bash
root@1ce9f640478d:/#
上面的命令將會創建一個名為ovcer_the_container的容器。對於一個合法的容器的名稱來說只可以包括以下字符:小寫字母a~z、大寫字母A-Z、數字0~9、下劃線、圓點、橫線。
上面就是Linux使用Docker容器的方法介紹了,在使用命令創建Docker容器後,就可以使用命令對Docker容器進行命名了。