docker筑基篇-01-docker基础命令及常用选项

docker 基础命令
info version

ps

inspect

rm

start restart

stop

attach

logs

top

exec

run命令
常用选项

示例一

示例二

示例三

1 docker 基础命令

info | version

# 查看docker总体信息
[root@h1 ~]# docker info
Containers: 1
Images: 42
Storage Driver: devicemapper
Pool Name: docker-253:0-395232-pool
Pool Blocksize: 65.54 kB
Backing Filesystem: extfs
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 2.516 GB
Data Space Total: 107.4 GB
Data Space Available: 29.24 GB
Metadata Space Used: 3.273 MB
Metadata Space Total: 2.147 GB
Metadata Space Available: 2.144 GB
Udev Sync Supported: true
Deferred Removal Enabled: false
Data loop file: /var/lib/docker/devicemapper/devicemapper/data
Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
Library Version: 1.02.117-RHEL6 (2016-08-15)
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 2.6.32-642.6.1.el6.x86_64
Operating System: <unknown>
CPUs: 1
Total Memory: 1.818 GiB
Name: h1
ID: KEQG:W5MZ:K5D3:RQRU:UUCV:SMGZ:NNQZ:BKVI:SZUS:HFEV:FTA7:GAI7

# 版本信息
[root@h1 ~]# docker version
Client version: 1.7.1
Client API version: 1.19
Go version (client): go1.4.2
Git commit (client): 786b29d/1.7.1
OS/Arch (client): linux/amd64
Server version: 1.7.1
Server API version: 1.19
Go version (server): go1.4.2
Git commit (server): 786b29d/1.7.1
OS/Arch (server): linux/amd64

# 版本信息
[root@h1 ~]# docker -v
Docker version 1.7.1, build 786b29d/1.7.1

ps

列出所有的container。不带参数的时候只是列出正在运行的container。

-a,--all
列出所有的容器
-s,--size
容器所占的空间大小
-l,--latest=true|false
只列出最近创建的容器，包括非运行的容器

inspect

可以查看比ps更加底层的信息。

-f, --format=""
利用go语言模板来格式化输出

rm

删除指定容器

-f,--force
强制删除，包括运行状态的容器。
-v,--volume
连带删除和容器关联的volume,谨慎操作。

start | restart

启动/重启指定的容器

docker start container-name

stop

停止一个正在运行的container

-t, --time=10
Number of
13cc3
seconds to wait for the container to stop before killing it. Default is 10 seconds.

attach

可以连接到一个正在运行的container上。

[root@h1 ~]# docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
5d54de7bd727        centos:6.8          "/bin/bash"         9 minutes ago       Up 22 seconds                           c1
[root@h1 ~]# docker attach c1
[root@5d54de7bd727 /]#

logs

可以监控一个正在运行的容器的日志记录

-f, --follow=true|false
实时监控日志输出. The default is false.
-t, --timestamps=true|false
日志记录中带上时间戳. The default is false.

docker logs -ft c1

top

exec

在一个正在运行的容器上执行命令

-d, --detach=true|false
在后台执行命令. The default is false.
-i, --interactive=true|false
执行交互式命令. The default is false
-u, --user=""
指定该命令以哪个用户的身份执行.

# 在名称为daemon_dev的容器上以后台任务的方式执行命令 "touch /etc/newfile"
docker exec -d daemon_dev touch /etc/newfile

# 在名称为daemon_dev的容器上打开一个交互式终端
docker exec -t -i daemon_dev /bin/bash

2 run命令

该命令会在一个新的容器中启动一个进程。该进程拥有自己的文件系统，网络组件，进程树等一个子系统应该具有的基础设施。

常用选项

-i, --interactive=false
容器的STDIN是否开启
-t, --tty=false
为容器分配一个伪tty终端
--name
为容器指定一个名称,名称的命必须是唯一的。可以通过名称来代替容器ID引用容器
-d, --detach=true|false
Detached mode:run the container in the background and print the new container ID.
The default is false.
--restart=no|always|on-failure[:max-retry]
设置container在退出的时候是否自动重启，以及重启的策略。
no：不自动重启
always：总是自动重启
on-failure：在退出码为非零的时候重启，并可以指定max-retry表示最多尝试重启的次数。

示例一

[root@h1 ~]# docker run -i -t centos:6.8 /bin/bash
Unable to find image 'centos:6.8' locally
6.8: Pulling from centos
386c6db8c14f: Pull complete
8986abc42d08: Pull complete
80e46367f846: Pull complete
80e46367f846: Pulling fs layer
Digest: sha256:233cbc13832f97e83773d2e4a6f9f3a81959bc9b5c1b03135d6bbd67a9db8b66
Status: Downloaded newer image for centos:6.8
[root@ec5bfab76e40 /]#

命令执行过程:

先本地查找是否存在镜像centos:6.8。如果本地不存在，去默认的DockerHub查找下载并将其保存在本地。

然后利用该镜像去创建一个新的容器。

当容器创建完成之后，就会执行我们传递给他的命令

/bin/bash

启动一个shell。可以看出命令提示符也从root@h1变成了root@ec5bfab76e40。

之后就可以像使用一个真正的centos操作系统来使用它了。只是这个操作系统只提供了一些最基本的命令:

[root@ec5bfab76e40 /]# hostname
ec5bfab76e40

[root@ec5bfab76e40 /]# cat /etc/hosts
172.17.0.1  ec5bfab76e40
127.0.0.1   localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

[root@ec5bfab76e40 /]# ifconfig
eth0      Link encap:Ethernet  HWaddr 02:42:AC:11:00:01
inet addr:172.17.0.1  Bcast:0.0.0.0  Mask:255.255.0.0
inet6 addr: fe80::42:acff:fe11:1/64 Scope:Link
UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
RX packets:6 errors:0 dropped:0 overruns:0 frame:0
TX packets:7 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:468 (468.0 b)  TX bytes:558 (558.0 b)

lo        Link encap:Local Loopback
inet addr:127.0.0.1  Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING  MTU:65536  Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

此时，在该终端中执行exit或者通过其他方式退出终端(/bin/bash结束)。该容器就会停止运行。

示例二

docker run --name daemon_dev -d centos:6.8 /bin/sh -c "while true;do echo hello world;sleep 1;done"

启动一个名称为daemon_dev的容器，该容器在后台运行，并一直打印hello world。

可以通过logs命令查看其日志。

[root@h1 ~]# docker logs -tf daemon_dev
2016-10-17T02:47:57.744262702Z hello world
2016-10-17T02:47:57.744262702Z hello world
2016-10-17T02:47:57.744262702Z hello world
2016-10-17T02:47:57.744262702Z hello world
2016-10-17T02:47:57.744262702Z hello world
2016-10-17T02:47:57.744262702Z hello world
2016-10-17T02:47:58.748041451Z hello world
2016-10-17T02:47:59.750740053Z hello world
# ……

利用exec执行命令：

[root@h1 ~]# docker exec -d daemon_dev touch /etc/newfile
[root@h1 ~]# docker exec -t -i daemon_dev /bin/bash
[root@833898befd96 /]# id
uid=0(root) gid=0(root) groups=0(root)
[root@833898befd96 /]# exit
exit
[root@h1 ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                CREATED             STATUS              PORTS               NAMES
833898befd96        centos:6.8          "/bin/sh -c 'while t   8 minutes ago       Up 8 minutes                            daemon_dev

停止该container:

docker stop daemon_dev

示例三

docker run --restart=always --name daemon_dev -d centos:6.8 /bin/sh -c "while true;do echo hello world;sleep 1;done"

该示例的基本功能和示例二类似，只不过该容器会自动重启。

查看更加详细的内部信息：

[root@h1 ~]# docker inspect daemon_dev
[
{
"Id": "efd88d4e01c380b5d70b0f96175e223b76cdc1be0b22697e08e8a58f786005cd",
"Created": "2016-10-17T03:05:06.213822618Z",
"Path": "/bin/sh",
"Args": [
"-c",
"while true;do echo hello world;sleep 1;done"
],
"State": {
"Running": true,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 7646,
"ExitCode": 0,
"Error": "",
"StartedAt": "2016-10-17T03:05:06.616292242Z",
"FinishedAt": "0001-01-01T00:00:00Z"
},
"Image": "80e46367f84650bdda8e3e638ba61be232e9881a8159bfed6d42f914597c68f4",
"NetworkSettings": {
"Bridge": "",
"EndpointID": "36b326748dd4914c72cb3b349aebeda4d2bd74f4a9fba497f02c8784f24c002d",
"Gateway": "172.17.42.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"HairpinMode": false,
"IPAddress": "172.17.0.12",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"LinkLocalIPv6Address": "",
"LinkLocalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:0c",
"NetworkID": "1839f9caada911ea3b980fde577641dabbef9b198b5da9850f686115753c293a",
"PortMapping": null,
"Ports": {},
"SandboxKey": "/var/run/docker/netns/efd88d4e01c3",
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null
},
"ResolvConfPath": "/var/lib/docker/containers/efd88d4e01c380b5d70b0f96175e223b76cdc1be0b22697e08e8a58f786005cd/resolv.conf",
"HostnamePath": "/var/lib/docker/containers/efd88d4e01c380b5d70b0f96175e223b76cdc1be0b22697e08e8a58f786005cd/hostname",
"HostsPath": "/var/lib/docker/containers/efd88d4e01c380b5d70b0f96175e223b76cdc1be0b22697e08e8a58f786005cd/hosts",
"LogPath": "/var/lib/docker/containers/efd88d4e01c380b5d70b0f96175e223b76cdc1be0b22697e08e8a58f786005cd/efd88d4e01c380b5d70b0f961
75e223b76cdc1be0b22697e08e8a58f786005cd-json.log",    "Name": "/daemon_dev",
"RestartCount": 0,
"Driver": "devicemapper",
"ExecDriver": "native-0.2",
"MountLabel": "",
"ProcessLabel": "",
"Volumes": {},
"VolumesRW": {},
"AppArmorProfile": "",
"ExecIDs": null,
"HostConfig": {
"Binds": null,
"ContainerIDFile": "",
"LxcConf": [],
"Memory": 0,
"MemorySwap": 0,
"CpuShares": 0,
"CpuPeriod": 0,
"CpusetCpus": "",
"CpusetMems": "",
"CpuQuota": 0,
"BlkioWeight": 0,
"OomKillDisable": false,
"Privileged": false,
"PortBindings": {},
"Links": null,
"PublishAllPorts": false,
"Dns": null,
"DnsSearch": null,
"ExtraHosts": null,
"VolumesFrom": null,
"Devices": [],
"NetworkMode": "bridge",
"IpcMode": "",
"PidMode": "",
"UTSMode": "",
"CapAdd": null,
"CapDrop": null,
"RestartPolicy": {
"Name": "always",
"MaximumRetryCount": 0
},
"SecurityOpt": null,
"ReadonlyRootfs": false,
"Ulimits": null,
"LogConfig": {
"Type": "json-file",
"Config": {}
},
"CgroupParent": ""
},
"Config": {
"Hostname": "efd88d4e01c3",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"PortSpecs": null,
"ExposedPorts": null,
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
],
"Cmd": [
"/bin/sh",
"-c",
"while true;do echo hello world;sleep 1;done"
],
"Image": "centos:6.8",
"Volumes": null,
"VolumeDriver": "",
"WorkingDir": "",
"Entrypoint": null,
"NetworkDisabled": false,
"MacAddress": "",
"OnBuild": null,
"Labels": {
"build-date": "2016-06-02",
"license": "GPLv2",
"name": "CentOS Base Image",
"vendor": "CentOS"
}
}
}
]
[root@h1 ~]#