docker执行第一个应用

概念科普

• Docker image：镜像是只读的，镜像中包含有需要运行的文件。镜像用来创建container，一个镜像可以运行多个container；镜像可以通过Dockerfile创建，也可以从Docker hub/registry上下载。
• Docker container：容器是Docker的运行组件，启动一个镜像就是一个容器，容器是一个隔离环境，多个容器之间不会相互影响，保证容器中的程序运行在一个相对安全的环境中。
• Docker hub/registry: 共享和管理Docker镜像，用户可以上传或者下载上面的镜像，官方地址为https://registry.hub.docker.com/，也可以搭建自己私有的Docker registry。

运行第一个镜像

将image从仓库下载到本地

docker pull library/hello-world

执行命令docker images 查看所有镜像

[root@insure docker]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
redis latest 5958914cc558  weeks ago .9MB
centos latest 75835a67d134  months ago 200MB
hello-world latest 4ab4c602aa5e  months ago .84kB
redis 4.0. 8f2e175b3bd1  months ago 107MB

运行刚才下载的镜像

[root@insure docker]# docker run hello-world

Hello from Docker!
This message shows that your installation appears to be working correctly.

To generate this message, Docker took the following steps:
 . The Docker client contacted the Docker daemon.
 . The Docker daemon pulled the "hello-world" image from the Docker Hub.
    (amd64)
 . The Docker daemon created a new container from that image which runs the
    executable that produces the output you are currently reading.
 . The Docker daemon streamed that output to the Docker client, which sent it
    to your terminal.

To try something more ambitious, you can run an Ubuntu container with:
 $ docker run -it ubuntu bash

Share images, automate workflows, and more with a free Docker ID:
 https://hub.docker.com/

For more examples and ideas, visit:
 https://docs.docker.com/get-started/

到此，我们第一个镜像运行成功。

现在我们删除所有的容器和镜像，保持一个干净的环境

首先删除容器，因为容器包含在镜像之内，一个镜像可以有很多容器

[root@insure docker]# docker ps -a
CONTAINER ID        IMAGE               COMMAND                  CREATED              STATUS                          PORTS               NAMES
b13eb6f29cb1        hello-world         "/hello"                 About a minute ago   Exited () About a minute ago                       blissful_benz
356502c8cbfd        centos:latest       "java -jar /usr/clai…"    hours ago         Created                                             claimdashboardtest
f5f8aa391da0        centos:latest       "/bin/bash"               weeks ago          Up  weeks                                          test-centos
[root@insure docker]# docker rm b13eb6f29cb1
b13eb6f29cb1
[root@insure docker]# docker rm 356502c8cbfd
356502c8cbfd
[root@insure docker]# docker f5f8aa391da0
docker: 'f5f8aa391da0' is not a docker command.
See 'docker --help'
[root@insure docker]# docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
f5f8aa391da0        centos:latest       "/bin/bash"          weeks ago         Up  weeks                              test-centos

删除镜像文件

[root@insure docker]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
redis               latest              5958914cc558         weeks ago         .9MB
centos              latest              75835a67d134         months ago        200MB
hello-world         latest              4ab4c602aa5e         months ago        .84kB
redis               4.0.               8f2e175b3bd1         months ago       107MB
[root@insure docker]# docker rmi 5958914cc558
Untagged: redis:latest
Untagged: redis@sha256:f57d1597d038a742dfba6acfaf48b10e6383466eea2aef95d1ee76f32633f959
Deleted: sha256:5958914cc55880091b005658a79645a90fd44ac6a33abef25d6be87658eb9599
Deleted: sha256:2034be36bd0f105ea0b4cbb124a96fa434fda3ce9c32dddcf38f1b6e5699ac91
Deleted: sha256:c2d3730f64b8e231f59d86ac8bdf6de3e62538a5b0030c9a37bf1cf21241ec76
Deleted: sha256:1a869407b0486b83e44fcec89fc7b12935c23caea8768e0e9402df67a01f4ffe
Deleted: sha256:1568b09301049abf7ed4b38406ce96465f2145af91428d9efa8c8c0dc53297fa
Deleted: sha256:42bd21f043c373312ccf3f31fcfeabf596497421e9ff0103b6fb7dc764de631e
Deleted: sha256:ef68f6734aa485edf13a8509fe60e4272428deaf63f446a441b79d47fc5d17d3
[root@insure docker]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
centos              latest              75835a67d134         months ago        200MB
hello-world         latest              4ab4c602aa5e         months ago        .84kB
redis               4.0.               8f2e175b3bd1         months ago       107MB

上面简单的练习了一下，镜像的下载和删除。

下面正式进入我们的目标文件------------jar

第一步

拉取openjdk镜像

[root@insure dockerfile]# docker pull openjdk
Using default tag: latest
latest: Pulling from library/openjdk
16e82e17faef: Pull complete
117dc02416a3: Pull complete
7e4c717259ac: Pull complete
7a518b8f48be: Pull complete
add32d44f708: Pull complete
a0158fa08543: Pull complete
eacd9302ecfd: Pull complete
8f9d52bf6cde: Pull complete
Digest: sha256:2cbb95c7479634c53bc2be243554a98d6928c189360fa958d2c970974e7f131f
Status: Downloaded newer image for openjdk:latest
[root@insure dockerfile]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
openjdk             latest              8e7eacedab93         weeks ago         986MB
centos              latest              75835a67d134         months ago        200MB

第二步编写dockerfile文件

#centos:latest 分别是镜像和版本号
FROM openjdk:latest

#将文件<src>拷贝到container的文件系统对应的路径<dest>
ADD claimdashboard-0.0.-SNAPSHOT.jar app.jar

#RUN命令将在当前image中执行任意合法命令并提交执行结果。命令执行提交后，就会自动执行Dockerfile中的下一个指令
RUN bash -c 'touch /app.jar'

ENTRYPOINT ["java","-jar","/app.jar"]

第三步生成镜像

[root@insure dockerfile]# sudo docker build -t="dashboard" .
Sending build context to Docker daemon  .15MB
Step / : FROM openjdk:latest
 ---> 8e7eacedab93
Step / : ADD claimdashboard-0.0.-SNAPSHOT.jar app.jar
 ---> ea0688f6b7cb
Step / : RUN bash -c 'touch /app.jar'
 ---> Running in e97e88a2fc96
Removing intermediate container e97e88a2fc96
 ---> 4d3d3cc9f9ce
Step / : ENTRYPOINT ["java","-jar","/app.jar"]
 ---> Running in 9fa1b0191846
Removing intermediate container 9fa1b0191846
 ---> 4762105b8815
Successfully built 4762105b8815
Successfully tagged dashboard:latest

[root@insure dockerfile]# docker images     查看已经的镜像
REPOSITORY TAG IMAGE ID CREATED SIZE
dashboard latest 4762105b8815 3 minutes ago 1.07GB
openjdk latest 8e7eacedab93 2 weeks ago 986MB
centos latest 75835a67d134 2 months ago 200MB

注意：命令后面要带上.  -t表给镜像命名为dashboard

第四步  启动容器

[root@insure dockerfile]# docker run -d -p : dashboard
0924d9762dccb860e3d4869f27ed8dd6c7b9f69ad25ad368c83ec036e61a7ee0
[root@insure dockerfile]# docker ps -a  查看已有的容器
CONTAINER ID        IMAGE               COMMAND                CREATED             STATUS              PORTS                    NAMES
0924d9762dcc        dashboard           "java -jar /app.jar"    seconds ago       Up  seconds        0.0.0.0:->/tcp   sleepy_ptolemy
f5f8aa391da0        centos:latest       "/bin/bash"             weeks ago         Up  minutes                                test-centos

命令解析docker run -d -p 8070:8070 dashboard

docker--专有命令 run--表示运行容器 -d 表示后台运行

-p表示端口 前一个端口是外部浏览器访问的端口 后一个端口是内部的端口 两个端口可以不一样

dashboard 容器的名字

第五步 用postman测试效果

到此第一个在docker容器上的jar运行成功并测试通过

1.查看所有的容器ip和名字

docker inspect --format='{{.Name}} - {{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' $(docker ps -aq)

docker run -tid --net=host -v /opt/pj/business.jar:/usr/business.jar --name business java:8u111 java -jar /usr/business.jar

-t: 为container分配一个伪终端(pseudo-tty)，并绑定到容器的标准输入上

-i: 让容器的标准输入保持打开

-d: 使容器在后台以守护态（Daemonized）形式运行

--net=host 使用host模式的容器可以直接使用docker host的IP地址与外界通信

-v /usr/springboot-1.jar:/usr/springboot-1.jar 表示将宿主主机的jar文件，映射到容器中（分号前为宿主主机的路径，分号后为容器中的路径）

--name business表示为该容器取一个全局唯一的名称，这里我取的名称为business

java:8u111 表示镜像文件的名称和tag

java -jar /usr/business.jar 表示运行jar包，注意：这里的jar包为容器中的位置，是通过前面的-v属性映射的