Docker usage basics

centos 6.x x64 
  首先要导入epel
  https://fedoraproject.org/wiki/EPEL#How_can_I_use_these_extra_packages.3F
  yum install -y docker-io

centos 7.x x64
  直接安装
  yum install -y docker

[root@db-172-16-3-221 ~]# service docker start

[root@db-172-16-3-221 ~]# docker info
Containers: 5
Images: 104
Storage Driver: devicemapper
 Pool Name: docker-8:49-17826869-pool
 Data file: /var/lib/docker/devicemapper/devicemapper/data
 Metadata file: /var/lib/docker/devicemapper/devicemapper/metadata
 Data Space Used: 2531.7 Mb
 Data Space Total: 102400.0 Mb
 Metadata Space Used: 4.1 Mb
 Metadata Space Total: 2048.0 Mb
Execution Driver: native-0.2
Kernel Version: 2.6.32-431.el6.x86_64
Username: digoal
Registry: [https://index.docker.io/v1/]

[root@db-172-16-3-221 ~]# docker search centos
NAME                                            DESCRIPTION                                     STARS     OFFICIAL   AUTOMATED
centos                                          The official build of CentOS.                   556       [OK]   
........
[root@db-172-16-3-221 ~]# docker pull centos
Pulling repository centos
68edf809afe7: Download complete 
504a65221a38: Download complete 
87e5b6b3ccc1: Download complete 
511136ea3c5a: Download complete 
5b12ef8fd570: Download complete 

查看本地镜像, 如果不在本地, 会自动从docker hub下载到本地, 
镜像是只读的, 可以基于镜像启动container
[root@db-172-16-3-221 ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             VIRTUAL SIZE
digoal/postgres     9.3.5               a7ef5455170d        21 hours ago        212.9 MB
postgres            9.4                 68b6ddf9ca08        8 days ago          213.6 MB
postgres            9.4-beta3           68b6ddf9ca08        8 days ago          213.6 MB
postgres            9.3.5               935836384c52        8 days ago          212.9 MB
postgres            latest              935836384c52        8 days ago          212.9 MB
postgres            9.3                 935836384c52        8 days ago          212.9 MB
postgres            9                   935836384c52        8 days ago          212.9 MB
postgres            9.2                 2a9ab0b9fa56        8 days ago          212.7 MB
postgres            9.2.9               2a9ab0b9fa56        8 days ago          212.7 MB
postgres            9.1.14              ee60947f6805        8 days ago          212.1 MB
postgres            9.1                 ee60947f6805        8 days ago          212.1 MB
postgres            9.0                 f29be88283f6        8 days ago          211.5 MB
postgres            9.0.18              f29be88283f6        8 days ago          211.5 MB
postgres            8                   c57c14beb696        8 days ago          211 MB
postgres            8.4                 c57c14beb696        8 days ago          211 MB
postgres            8.4.22              c57c14beb696        8 days ago          211 MB
postgres            9.4-beta2           bf872395e1d4        3 weeks ago         213.6 MB
centos              centos5             504a65221a38        4 weeks ago         467.1 MB
centos              centos6             68edf809afe7        4 weeks ago         212.7 MB
centos              centos7             87e5b6b3ccc1        4 weeks ago         224 MB
centos              latest              87e5b6b3ccc1        4 weeks ago         224 MB
启动container
用法 : 
[root@db-172-16-3-221 ~]# docker help run

Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...]

Run a command in a new container

  -a, --attach=[]            Attach to stdin, stdout or stderr.
  -c, --cpu-shares=0         CPU shares (relative weight)
  --cidfile=""               Write the container ID to the file
  --cpuset=""                CPUs in which to allow execution (0-3, 0,1)
  -d, --detach=false         Detached mode: Run container in the background, print new container id
  --dns=[]                   Set custom dns servers
  --dns-search=[]            Set custom dns search domains
  -e, --env=[]               Set environment variables
  --entrypoint=""            Overwrite the default entrypoint of the image
  --env-file=[]              Read in a line delimited file of ENV variables
  --expose=[]                Expose a port from the container without publishing it to your host
  -h, --hostname=""          Container host name
  -i, --interactive=false    Keep stdin open even if not attached
  --link=[]                  Add link to another container (name:alias)
  --lxc-conf=[]              (lxc exec-driver only) Add custom lxc options --lxc-conf="lxc.cgroup.cpuset.cpus = 0,1"
  -m, --memory=""            Memory limit (format: <number><optional unit>, where unit = b, k, m or g)
  --name=""                  Assign a name to the container
  --net="bridge"             Set the Network mode for the container
                               'bridge': creates a new network stack for the container on the docker bridge
                               'none': no networking for this container
                               'container:<name|id>': reuses another container network stack
                               'host': use the host network stack inside the container.  Note: the host mode gives the container full access to local system services such as D-bus and is therefore considered insecure.
  -P, --publish-all=false    Publish all exposed ports to the host interfaces
  -p, --publish=[]           Publish a container's port to the host
                               format: ip:hostPort:containerPort | ip::containerPort | hostPort:containerPort
                               (use 'docker port' to see the actual mapping)
  --privileged=false         Give extended privileges to this container
  --rm=false                 Automatically remove the container when it exits (incompatible with -d)
  --sig-proxy=true           Proxify received signals to the process (even in non-tty mode). SIGCHLD is not proxied.
  -t, --tty=false            Allocate a pseudo-tty
  -u, --user=""              Username or UID
  -v, --volume=[]            Bind mount a volume (e.g., from the host: -v /host:/container, from docker: -v /container)
  --volumes-from=[]          Mount volumes from the specified container(s)
  -w, --workdir=""           Working directory inside the container

[root@db-172-16-3-221 ~]# docker run -d --name hello postgres:9.3.5
358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105
[root@db-172-16-3-221 ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                CREATED             STATUS              PORTS               NAMES
358c3b256ed3        postgres:9          /docker-entrypoint.s   4 seconds ago       Up 3 seconds        5432/tcp            hello

[root@db-172-16-3-221 ~]# docker run -t -i --name hello123 postgres:9.3.5 /bin/bash
root@fc2bb8e60b49:/#

[root@db-172-16-3-221 ~]# service docker stop
Stopping docker: [  OK  ]
使用docker -d启动后台服务.
[root@db-172-16-3-221 ~]# docker -d
2014/10/30 13:39:21 WARNING: You are running linux kernel version 2.6.32-431.el6.x86_64, which might be unstable running docker. Please upgrade your kernel to 3.8.0.
2014/10/30 13:39:21 docker daemon: 1.1.2 d84a070/1.1.2; execdriver: native; graphdriver: 
[ce9e52b6] +job serveapi(unix:///var/run/docker.sock)
[ce9e52b6] +job initserver()
[ce9e52b6.initserver()] Creating server
2014/10/30 13:39:21 Listening for HTTP on unix (/var/run/docker.sock)
[ce9e52b6] +job init_networkdriver()
[ce9e52b6] -job init_networkdriver() = OK (0)
Loading containers: ..........[error] driver.go:140 Warning: error unmounting device ca64905e843ab439926406d19378d4c5c7419bb584a4379a39890efea63ce23e: UnmountDevice: device not-mounted id ca64905e843ab439926406d19378d4c5c7419bb584a4379a39890efea63ce23e


..[error] driver.go:140 Warning: error unmounting device 8238bc46c1dad147536006be4f08561b87ad014b59d928b8521263cd5b96cb4d: UnmountDevice: device not-mounted id 8238bc46c1dad147536006be4f08561b87ad014b59d928b8521263cd5b96cb4d


.[error] driver.go:140 Warning: error unmounting device aab6a732ddbc43e2cab846aede454c7a39342412852691982231d0e000eb5d0a: UnmountDevice: device not-mounted id aab6a732ddbc43e2cab846aede454c7a39342412852691982231d0e000eb5d0a


.[error] driver.go:140 Warning: error unmounting device 358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105: UnmountDevice: device not-mounted id 358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105


..[error] driver.go:140 Warning: error unmounting device 7c99c4f4a01f0640dd1f236d3f597269a22f922d5292119cddd23ace1f082fc0: UnmountDevice: device not-mounted id 7c99c4f4a01f0640dd1f236d3f597269a22f922d5292119cddd23ace1f082fc0


..[error] driver.go:140 Warning: error unmounting device edae35acc741902a34b26e66e567bc7a3639981dd38967620b08ccbb37f0223c: UnmountDevice: device not-mounted id edae35acc741902a34b26e66e567bc7a3639981dd38967620b08ccbb37f0223c


[ce9e52b6] +job release_interface(358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105)
No network information to release for 358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105
[ce9e52b6] -job release_interface(358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105) = ERR (1)
[error] driver.go:140 Warning: error unmounting device 358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105: UnmountDevice: device not-mounted id 358c3b256ed3eb2465b4bcdf95ffef6ab8449452d9b68dc26d22649965e22105


: done.
[ce9e52b6.initserver()] Creating pidfile
[ce9e52b6.initserver()] Setting up signal traps
[ce9e52b6] -job initserver() = OK (0)
[ce9e52b6] +job acceptconnections()
[ce9e52b6] -job acceptconnections() = OK (0)

删除一个container 可以看到 docker 控制台的输出 : 
[root@db-172-16-3-221 ~]# docker rm b3e755c4b710
b3e755c4b710
控制台输出
2014/10/30 13:41:10 DELETE /v1.13/containers/b3e755c4b710
[ce9e52b6] +job container_delete(b3e755c4b710)
[ce9e52b6] -job container_delete(b3e755c4b710) = OK (0)

启动docker server时改变docker监听 : 
       -H, --host=[unix:///var/run/docker.sock]: tcp://[host:port] to bind or unix://[/path/to/socket]  to  use.   The
       socket(s) to bind to in daemon mode specified using one or more tcp://host:port, unix:///path/to/socket, fd://*
       or fd://socketfd.
例如
[root@db-172-16-3-221 ~]# docker -d -H tcp://0.0.0.0:9999 -H unix:///tmp/.docker.9999.sock
2014/10/30 13:51:30 WARNING: You are running linux kernel version 2.6.32-431.el6.x86_64, which might be unstable running docker. Please upgrade your kernel to 3.8.0.
2014/10/30 13:51:30 docker daemon: 1.1.2 d84a070/1.1.2; execdriver: native; graphdriver: 
[bb265d31] +job serveapi(tcp://0.0.0.0:9999, unix:///tmp/.docker.9999.sock)
[bb265d31] +job initserver()
[bb265d31.initserver()] Creating server
2014/10/30 13:51:30 Listening for HTTP on tcp (0.0.0.0:9999)
2014/10/30 13:51:30 /!\ DON'T BIND ON ANOTHER IP ADDRESS THAN 127.0.0.1 IF YOU DON'T KNOW WHAT YOU'RE DOING /!\
2014/10/30 13:51:30 Listening for HTTP on unix (/tmp/.docker.9999.sock)
[bb265d31] +job init_networkdriver()
[bb265d31] -job init_networkdriver() = OK (0)
Loading containers: ......: done.
[bb265d31.initserver()] Creating pidfile
[bb265d31.initserver()] Setting up signal traps
[bb265d31] -job initserver() = OK (0)
[bb265d31] +job acceptconnections()
[bb265d31] -job acceptconnections() = OK (0)

例如, 连接到监听为9999端口的docker server : 
[root@db-172-16-3-221 ~]# docker -H 127.0.0.1:9999 ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES

[root@db-172-16-3-221 ~]# docker help run
Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...]
Run a command in a new container
  -d, --detach=false         Detached mode: Run container in the background, print new container id
例如 : 
[root@db-172-16-3-221 ~]# docker -H 127.0.0.1:9999 run -d postgres:9.3.5
611a769c1c468d11178a341959109dc0ee3ae581edb2103cf8e1379e8cc077c8

[root@db-172-16-3-221 ~]# docker -H 127.0.0.1:9999 ps -a
CONTAINER ID        IMAGE               COMMAND                CREATED             STATUS                      PORTS               NAMES
611a769c1c46        postgres:9          /docker-entrypoint.s   17 seconds ago      Up 16 seconds               5432/tcp            mad_ritchie           
358c3b256ed3        postgres:9          /docker-entrypoint.s   18 minutes ago      Exited (0) 15 minutes ago   5432/tcp            elegant_brattain      
ca64905e843a        postgres:9          /docker-entrypoint.s   27 hours ago        Exited (0) 15 minutes ago   5432/tcp            determined_rosalind   
aab6a732ddbc        postgres:9          /docker-entrypoint.s   44 hours ago        Exited (0) 15 minutes ago   5432/tcp            jolly_fermi           
edae35acc741        postgres:9          /docker-entrypoint.s   44 hours ago        Exited (0) 15 minutes ago   5432/tcp            kickass_poincare      
7c99c4f4a01f        postgres:9          /docker-entrypoint.s   44 hours ago        Exited (0) 15 minutes ago   5432/tcp            hopeful_tesla         
8238bc46c1da        postgres:9          /docker-entrypoint.s   44 hours ago        Exited (0) 15 minutes ago   5432/tcp            prickly_bohr    

[root@db-172-16-3-221 ~]# docker stop be885c1251cc
be885c1251cc
[root@db-172-16-3-221 ~]# docker restart be885c1251cc
be885c1251cc
[root@db-172-16-3-221 ~]# docker stop be885c1251cc
be885c1251cc
[root@db-172-16-3-221 ~]# docker kill be885c1251cc
be885c1251cc
[root@db-172-16-3-221 ~]# docker rm be885c1251cc
be885c1251cc

[root@db-172-16-3-221 ~]# docker help run
Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...]
Run a command in a new container
  --dns=[]                   Set custom dns servers
  --dns-search=[]            Set custom dns search domains
  --net="bridge"             Set the Network mode for the container
                               'bridge': creates a new network stack for the container on the docker bridge
                               'none': no networking for this container
                               'container:<name|id>': reuses another container network stack
                               'host': use the host network stack inside the container.  Note: the host mode gives the container full access to local system services such as D-bus and is therefore considered insecure.
启动container时指定即可.
如果要让DOCKER服务端自动改写iptables运行container访问外网, 可以使用--net="host"
例如 : 
[root@db-172-16-3-221 ~]# docker run -t -i --rm --net="host" centos:centos7 /bin/bash
bash-4.2# ping www.baidu.com
PING www.a.shifen.com (115.239.210.27) 56(84) bytes of data.
64 bytes from 115.239.210.27: icmp_seq=1 ttl=56 time=2.44 ms
64 bytes from 115.239.210.27: icmp_seq=2 ttl=56 time=2.40 ms

12. container 端口映射
docker help run
  -P, --publish-all=false    Publish all exposed ports to the host interfaces
  -p, --publish=[]           Publish a container's port to the host
                               format: ip:hostPort:containerPort | ip::containerPort | hostPort:containerPort
                               (use 'docker port' to see the actual mapping)

动态映射
[root@db-172-16-3-221 ~]# docker run -d -P postgres:9.3.5
d76f1559ca83a649895a841ddc2366169d958ff14fb65efc6d276bdeeeb9f1b0
[root@db-172-16-3-221 ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                CREATED             STATUS              PORTS                     NAMES
d76f1559ca83        postgres:9          /docker-entrypoint.s   3 seconds ago       Up 1 seconds        0.0.0.0:49153->5432/tcp   kickass_wilson
指定本地端口
[root@db-172-16-3-221 ~]# docker run -d -p 0.0.0.0:9999:5432/tcp postgres:9.3.5
4cc03cffa249aee4992287228273c88521e41699b4295afa73ace5716ff844bc
[root@db-172-16-3-221 ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                CREATED              STATUS              PORTS                     NAMES
4cc03cffa249        postgres:9          /docker-entrypoint.s   4 seconds ago        Up 2 seconds        0.0.0.0:9999->5432/tcp    stupefied_euclid 

如果对container做了一些修改, 例如安装了一些包, 并且想在下次运行container时不需要重复安装这个动作, 那么可以把当前的container保存为image, 下次启动时启动保存的image即可.
例如 : 
首先启动一个container, 命名为digoal123
[root@db-172-16-3-221 ~]# docker run --net="host" -t -i --name="digoal123" centos:centos7 /bin/bash
bash-4.2# yum install -y vim
打包帮助
[root@db-172-16-3-221 ~]# docker help commit

Usage: docker commit [OPTIONS] CONTAINER [REPOSITORY[:TAG]]

Create a new image from a container's changes

  -a, --author=""     Author (e.g., "John Hannibal Smith <hannibal@a-team.com>")
  -m, --message=""    Commit message
  -p, --pause=true    Pause container during commit
打包, 放到本地 digoal/postgres:digoal123_vim
[root@db-172-16-3-221 ~]# docker commit -a "digoal" -m "install vim" -p digoal123 digoal/postgres:digoal123_vim
1ac234066815825d8a79931d11d45624a242d67a29ad3d3789b56b577fa51a91
接下来可以允许该image, 可以看到vim已经安装好了
[root@db-172-16-3-221 ~]# docker run -t -i --rm digoal/postgres:digoal123_vim /bin/bash
bash-4.2# which vim
/usr/bin/vim

这个首先要注册docker hub账号, 然后login.
[root@db-172-16-3-221 ~]# docker login
Username: digoal
Password: 
Email: xxx@xx.xx
Login Succeeded
最后就是上传
[root@db-172-16-3-221 ~]# docker push digoal/postgres:digoal123_vim