Docker入门
Docker运行信息
使用sudo docker info，将会发送命令给DockerDaemon，返回Docker运行的信息。
Containers: 2
Running: 0
Paused: 0
Stopped: 2
Images: 2
Server Version: 17.03.1-ce
Storage Driver: aufs
Root Dir: /var/lib/docker/aufs
Backing Filesystem: extfs
Dirs: 10
Dirperm1 Supported: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 4ab9917febca54791c5f071a9d1f404867857fcc
runc version: 54296cf40ad8143b62dbcaa1d90e520a2136ddfe
init version: 949e6fa
Security Options:
apparmor
seccomp
Profile: default
Kernel Version: 4.8.0-49-generic
Operating System: Ubuntu 16.04.2 LTS
OSType: linux
Architecture: x86_64
CPUs: 8
Total Memory: 31.36 GiB
Name: weipeng2k-workstation
ID: 5ZXX:RICR:KQKY:BFOY:QPRK:W4TB:TJQL:R74Q:ABZB:X3CV:GVWF:YSGB
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
WARNING: No swap limit support
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false
该命令会返回所有容器和镜像的数量
存储器的驱动等配置信息
运行容器
使用sudo docker run -i -t ubuntu /bin/bash，docker run命令提供了Docker容器的创建到启动的功能。
sudo docker run -i -t ubuntu:16.04 /bin/bash，可以选择启动ubuntu镜像中tag为16.04的版本。
-i标志，保证容器STDIN是开启的，-t使得创建的容器分配了一个tty终端。
由于运行的ubuntu的
sources.list中是美国地址，在进行软件安装的时候非常慢，因此我们基于ubuntu构建一个使用中国仓库的ubuntu。在
src/chapter3中创建一个目录ubuntu
cp /etc/apt/sources.list .
vi Dockerfile
Dockerfile内容为：
FROM ubuntu:16.04
COPY sources.list /etc/apt/
创建了一个镜像，从官方
ubuntu:16.04派生，将当前的sources.list拷贝到/etc/apt/目录下，替换旧有的sources.list该
sources.list内容是来自cn的。
下面使用sudo docker build -t "weipeng2k/ubuntu:16.04" .，创建一个镜像。
然后使用sudo docker run -i -t weipeng2k/ubuntu:16.04 /bin/bash运行一个容器，登录其中，安装一下工具。
可以看到是从中国仓库中下载，速度很快。
root@34fe3f085d18:/# apt-get install net-tools
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
net-tools
0 upgraded, 1 newly installed, 0 to remove and 9 not upgraded.
Need to get 175 kB of archives.
After this operation, 725 kB of additional disk space will be used.
Get:1 http://cn.archive.ubuntu.com/ubuntu xenial/main amd64 net-tools amd64 1.60-26ubuntu1 [175 kB]
Fetched 175 kB in 0s (653 kB/s)
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package net-tools.
(Reading database ... 4764 files and directories currently installed.)
Preparing to unpack .../net-tools_1.60-26ubuntu1_amd64.deb ...
Unpacking net-tools (1.60-26ubuntu1) ...
Setting up net-tools (1.60-26ubuntu1) ...
root@34fe3f085d18:/# ifconfig
eth0 Link encap:Ethernet HWaddr 02:42:ac:11:00:02
inet addr:172.17.0.2 Bcast:0.0.0.0 Mask:255.255.0.0
inet6 addr: fe80::42:acff:fe11:2/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:9771 errors:0 dropped:0 overruns:0 frame:0
TX packets:5376 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:14717960 (14.7 MB) TX bytes:362791 (362.7 KB)
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:1
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
使用sudo docker ps可以查看运行的容器，如果容器已经停止了将不会展示，但是可以通过sudo docker ps -a查看所有的容器。
$ sudo docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
34fe3f085d18 weipeng2k/ubuntu:16.04 "/bin/bash" 38 minutes ago Exited (0) 15 minutes ago vigilant_shannon
61fba4e07526 ubuntu "/bin/bash" About an hour ago Exited (0) 50 minutes ago laughing_rosalind
93cca381d115 ubuntu "bash" 4 days ago Exited (0) 4 days ago jolly_kirch
3e8954daff1b hello-world "/hello" 4 days ago Exited (0) 4 days ago agitated_einstein
可以看到很多有用的信息，比如容器ID，来自哪个镜像，以及容器执行的命令和状态。
容器命名
之前通过docker ps看到的的列表，NAMES属性非常怪异，因为是Docker随机生成的，如果我们需要指定名称可以通过sudo docker --name container_name -i -t weipeng2k/ubuntu:16.04 uname -a来进行。
$ sudo docker run --name container_name weipeng2k/ubuntu:16.04 uname -a
Linux 91b9e178ca14 4.8.0-49-generic #52~16.04.1-Ubuntu SMP Thu Apr 20 10:55:59 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
$ sudo docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
91b9e178ca14 weipeng2k/ubuntu:16.04 "uname -a" 16 seconds ago Exited (0) 16 seconds ago container_name
34fe3f085d18 weipeng2k/ubuntu:16.04 "/bin/bash" 44 minutes ago Exited (0) 21 minutes ago vigilant_shannon
61fba4e07526 ubuntu "/bin/bash" About an hour ago Exited (0) 56 minutes ago laughing_rosalind
93cca381d115 ubuntu "bash" 4 days ago Exited (0) 4 days ago jolly_kirch
3e8954daff1b hello-world "/hello" 4 days ago Exited (0) 4 days ago agitated_einstein
一般来说指定名称非常有用，我们可以通过名称替代ID。
重新启动
Docker容器在命令执行完毕后，就会自动退出，如果我们想重新启动容器，可以通过sudo docker start container_name来完成容器的再启动。
$ sudo docker start -i container_name
Linux 91b9e178ca14 4.8.0-49-generic #52~16.04.1-Ubuntu SMP Thu Apr 20 10:55:59 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
守护式容器
守护式容器不是创建一个交互式的容器，适合运行应用和服务。
在chapter3/daemon_echo中创建了一个镜像。
sudo docker build -t "weipeng2k/daemon_echo" .构建一个daemon_echo。这个容器编译了一个Test.java，并运行它，它每隔一秒打印一次hello, world.。
public class Test {
public static void main(String[] args) throws Exception {
while(true) {
System.out.println("hello world.");
Thread.sleep(1000);
}
}
}
sudo docker run -name daemon_echo -d weipeng2k/daemon_echo，以daemon形式在后台运行，如果没有-d，将会在前台运行。
我们先用非daemon方式启动，可以看到它在前台启动，如果使用ctrl + C，将退出当前进程。
$ sudo docker run --name daemon_echo2 weipeng2k/daemon_echo
hello world.
hello world.
hello world.
hello world.
hello world.
hello world.
hello world.
hello world.
hello world.
hello world.
而使用-d运行，docker进程在后台运行，前台只是返回了一个Docker容器的ID。
可以通过sudo docker logs -f daemon_echo观察容器内的日志输出。
观察容器
可以通过sudo docker top daemon_echo来查看容器内的进程。
$ sudo docker top daemon_echo
UID PID PPID C STIME TTY TIME CMD
root 18408 18390 0 22:50 ? 00:00:00 java Test
可以通过sudo docker exec 来执行命令，比如：
$ sudo docker exec -i -t daemon_echo /bin/bash
root@94df9b5f5e8b:~/app# ls
Test.class Test.java
root@94df9b5f5e8b:~/app# jps
1 Test
43 Jps
root@94df9b5f5e8b:~/app# jps
1 Test
63 Jps
指定一个守护式容器，运行一个命令，这里启动了一个bash，并且连接上去。
可以通过sudo docker inspect来查看容器的详细信息。
$ sudo docker inspect daemon_echo
[
{
"Id": "94df9b5f5e8ba82900f9a01bca0e9e66815cdd01ca054421ce943590a58e4357",
"Created": "2017-05-06T14:21:45.492458772Z",
"Path": "java",
"Args": [
"Test"
],
"State": {
"Status": "exited",
"Running": false,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 0,
"ExitCode": 143,
"Error": "",
"StartedAt": "2017-05-06T14:50:44.525336192Z",
"FinishedAt": "2017-05-06T14:56:41.952696647Z"
},
"Image": "sha256:544097392791b51128724cd0dc317ee50c144981e1119248db4164c338e19f33",
"ResolvConfPath": "/var/lib/docker/containers/94df9b5f5e8ba82900f9a01bca0e9e66815cdd01ca054421ce943590a58e4357/resolv.conf",
"HostnamePath": "/var/lib/docker/containers/94df9b5f5e8ba82900f9a01bca0e9e66815cdd01ca054421ce943590a58e4357/hostname",
"HostsPath": "/var/lib/docker/containers/94df9b5f5e8ba82900f9a01bca0e9e66815cdd01ca054421ce943590a58e4357/hosts",
"LogPath": "/var/lib/docker/containers/94df9b5f5e8ba82900f9a01bca0e9e66815cdd01ca054421ce943590a58e4357/94df9b5f5e8ba82900f9a01bca0e9e66815cdd01ca054421ce943590a58e4357-json.log",
"Name": "/daemon_echo",
"RestartCount": 0,
"Driver": "aufs",
"MountLabel": "",
"ProcessLabel": "",
"AppArmorProfile": "",
"ExecIDs": null,
"HostConfig": {
"Binds": null,
"ContainerIDFile": "",
"LogConfig": {
"Type": "json-file",
"Config": {}
},
"NetworkMode": "default",
"PortBindings": {},
"RestartPolicy": {
"Name": "no",
"MaximumRetryCount": 0
},
"AutoRemove": false,
"VolumeDriver": "",
"VolumesFrom": null,
"CapAdd": null,
"CapDrop": null,
"Dns": [],
"DnsOptions": [],
"DnsSearch": [],
"ExtraHosts": null,
"GroupAdd": null,
"IpcMode": "",
"Cgroup": "",
"Links": null,
"OomScoreAdj": 0,
"PidMode": "",
"Privileged": false,
"PublishAllPorts": false,
"ReadonlyRootfs": false,
"SecurityOpt": null,
"UTSMode": "",
"UsernsMode": "",
"ShmSize": 67108864,
"Runtime": "runc",
"ConsoleSize": [
0,
0
],
"Isolation": "",
"CpuShares": 0,
"Memory": 0,
"NanoCpus": 0,
"CgroupParent": "",
"BlkioWeight": 0,
"BlkioWeightDevice": null,
"BlkioDeviceReadBps": null,
"BlkioDeviceWriteBps": null,
"BlkioDeviceReadIOps": null,
"BlkioDeviceWriteIOps": null,
"CpuPeriod": 0,
"CpuQuota": 0,
"CpuRealtimePeriod": 0,
"CpuRealtimeRuntime": 0,
"CpusetCpus": "",
"CpusetMems": "",
"Devices": [],
"DiskQuota": 0,
"KernelMemory": 0,
"MemoryReservation": 0,
"MemorySwap": 0,
"MemorySwappiness": -1,
"OomKillDisable": false,
"PidsLimit": 0,
"Ulimits": null,
"CpuCount": 0,
"CpuPercent": 0,
"IOMaximumIOps": 0,
"IOMaximumBandwidth": 0
},
"GraphDriver": {
"Name": "aufs",
"Data": null
},
"Mounts": [],
"Config": {
"Hostname": "94df9b5f5e8b",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
],
"Cmd": [
"java",
"Test"
],
"ArgsEscaped": true,
"Image": "weipeng2k/daemon_echo",
"Volumes": null,
"WorkingDir": "/root/app",
"Entrypoint": null,
"OnBuild": null,
"Labels": {}
},
"NetworkSettings": {
"Bridge": "",
"SandboxID": "fa457180ba8f22fc8b5458f8702680b2ef6f431cc04fa279bbc7ba29d3787afe",
"HairpinMode": false,
"LinkLocalIPv6Address": "",
"LinkLocalIPv6PrefixLen": 0,
"Ports": null,
"SandboxKey": "/var/run/docker/netns/fa457180ba8f",
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "",
"Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"MacAddress": "",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "59c20d993ec2ced31e66fade31e61cc619b62d46eb9c844f8bbf668c7075ff33",
"EndpointID": "",
"Gateway": "",
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": ""
}
}
}
}
]
删除容器
删除一个容器，可以使用sudo docker rm来进行，比如：
$ sudo docker rm daemon_echo
daemon_echo
只有停止的容器才能够被删除，如果没有停止，通过
sudo docker stop daemon_echo来停止一个容器sudo docker rm
sudo docker ps -a -q可以方便的删除所有容器。