[Docker] Docker 之 CentOS 环境安装

Docker 之 CentOS 环境安装

版本信息

• • 
    
• docker -v
  ​​ xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker -v Docker version 18.05.0-ce, build f150324 ​​
• uname -a
  ​​ [root@f7106025b994 /]# uname -a Linux f7106025b994 4.9.93-linuxkit-aufs #1 SMP Wed Jun 6 16:55:56 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux ​​
• 本地磁盘挂载(资源文件共享)
  ​​docker run -i -t -v ~/software:/mnt/software centos /bin/bash xiazhaoyangdeMacBook-Pro:/ xiazhaoyang$ cd ~/software xiazhaoyangdeMacBook-Pro:software xiazhaoyang$ ls jdk-8u172-linux-x64.tar.gz xiazhaoyangdeMacBook-Pro:software xiazhaoyang$ pwd /Users/xiazhaoyang/software ​​
• centos软件安装目录 /opt
  • 
    

安装jdk

解压

tar -zxvf /mnt/software/jdk-8u172-linux-x64.tar.gz  -C /opt

创建映射

ln -s /opt/jdk1.8.0_172 /opt/jdk

# 测试映射路径
ll /opt/jdk
/opt/jdk/bin/java -version

修改环境变量

vi /etc/profile

# JAVA_ENV_CONFIGURATION
export JAVA_HOME=/opt/jdk              
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib  
export PATH=${JAVA_HOME}/bin:$PATH

激活配置并测试

source /etc/profile

[root@7941a20a85b6 opt]# java -version
java version "1.8.0_172"
Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)

镜像操作

镜像上传

# 将本地容器提交为镜像
xiazhaoyangdeMacBook-Pro:software xiazhaoyang$ docker commit 7941a20a85b6 xiachaoyang/centos-java
sha256:905af87b4a5efcd0d7c5128700393d65f50c4575878cb250fae177c987d87964
xiazhaoyangdeMacBook-Pro:software xiazhaoyang$ docker images
REPOSITORY                TAG                 IMAGE ID            CREATED             SIZE
xiachaoyang/centos-java   latest              905af87b4a5e        18 seconds ago      587MB
centos                    latest              49f7960eb7e4        2 weeks ago         200MB
xiazhaoyangdeMacBook-Pro:software xiazhaoyang$

镜像验证

xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker images
    REPOSITORY                TAG                 IMAGE ID            CREATED             SIZE
    xiachaoyang/centos-java   latest              905af87b4a5e        10 minutes ago      587MB
    centos                    latest              49f7960eb7e4        2 weeks ago         200MB
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker run --rm xiachaoyang/centos-java /opt/jdk/bin/java -version
    java version "1.8.0_172"
    Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
    Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$

[备注]

1.  容器通过commit直接生成的镜像使用`docker run -i -t xiachaoyang/centos-java`启动镜像后,需要再次执行source /etc/profile 才能激活环境变量

[root@288652cb51f3 /]# java -version
    bash: java: command not found
    [root@288652cb51f3 /]# source /etc/profile
    [root@288652cb51f3 /]# java -version
    java version "1.8.0_172"
    Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
    Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)
    [root@288652cb51f3 /]#

推荐使用Dockerfile创建镜像

2.  启动镜像后可以多终端访问同一运行中容器

# 启动一个实例
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker run -i -t xiachaoyang/centos-java /bin/bash
    [root@288652cb51f3 /]#

    # 开启新终端查询实例ID并进入
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker ps
    CONTAINER ID        IMAGE                     COMMAND             CREATED             STATUS              PORTS               NAMES
    288652cb51f3        xiachaoyang/centos-java   "/bin/bash"         2 minutes ago       Up About a minute                       nifty_bhabha
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker attach 288652cb51f3
    [root@288652cb51f3 /]#

    # 测试运行中实例是否有变化
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker ps
    CONTAINER ID        IMAGE                     COMMAND             CREATED             STATUS              PORTS               NAMES
    288652cb51f3        xiachaoyang/centos-java   "/bin/bash"         2 minutes ago       Up 2 minutes                            nifty_bhabha
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$

3.  多个终端链接同一镜像，退出后整体退出。
所有操作都是并行的，A输入cmd1,B也同样出现cmd1

4.  基于centos进行的镜像操作，本地centos是否会发生变化，能否提交覆盖

不能,推送类似于git操作，需要权限。

xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker push centos
    The push refers to repository [docker.io/library/centos]
    bcc97fbfc9e1: Layer already exists
    errors:
    denied: requested access to the resource is denied
    unauthorized: authentication required

5.  对于本地库中镜像的操作(运行容器并修改部分东西)，能否覆盖提交，能否提交到仓库同名下，还是说需要利用tag进行标记？

可以覆盖更新镜像，参考下文:

​​创建本地镜像(commit、Dockerfile)​​

6.  同一镜像生成的不同ID的容器，互相之间不受影响，修改在退出后也不会保存

镜像推送

​​Docker Hub​​

• • 
    
• 创建DockerHub账号
• 创建仓库
• 推送本地镜像
  
• 
  

非必须，没有权限时需要登录

推送

xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker images
    REPOSITORY            TAG                 IMAGE ID            CREATED             SIZE
    xiachaoyang/env-jdk   latest              abe21e6640f3        13 hours ago        587MB
    centos                latest              49f7960eb7e4        2 weeks ago         200MB
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker push xiachaoyang/env-jdk
    The push refers to repository [docker.io/xiachaoyang/env-jdk]
    f65468761332: Pushed
    5ed6bb2dd837: Pushed
    bcc97fbfc9e1: Mounted from library/centos
    latest: digest: sha256:a7f0324eae38d9ce41389bccd43c92f3fa9d8a1a1dbe5ff52d6be978815fb267 size: 949

• 搜索镜像
  docker search xiaochaoyang/env-jdk
  Docker Hub会定时对已上传的镜像仓库进行索引，随后可通过​​docker search xiachaoyang/centos-java​​进行搜索自己推送到Docker Hub的镜像仓库

镜像功能测试

# 查询运行中容器
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker ps
    CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker run -i -t xiachaoyang/centos-java /bin/bash
    [root@288652cb51f3 /]#

Dockerfile 创建镜像

xiazhaoyangdeMacBook-Pro:Dockerfile         jdk-8u172-linux-x64.tar.gz
    xiazhaoyangdeMacBook-Pro:jdk-8u172-linux-x64 xiazhaoyang$ docker build -t xiachaoyang/centos-java .
    Sending build context to Docker daemon  190.9MB
    Step 1/7 : FROM centos:latest
    ---> 49f7960eb7e4
    Step 2/7 : MAINTAINER  "xiachaoyang"<xiazhaoyang@live.com>
    ---> Using cache
    ---> c1009b593364
    Step 3/7 : ADD jdk-8u172-linux-x64.tar.gz /opt
    ---> Using cache
    ---> 9c32f5eacb71
    Step 4/7 : RUN ln -s /opt/jdk-8u172-linux-x64 /opt/jdk
    ---> Running in 23a59c89c7be
    Removing intermediate container 23a59c89c7be
    ---> 99b3d5d9446c
    Step 5/7 : ENV JAVA_HOME /opt/jdk
    ---> Running in f70d6dd4dda2
    Removing intermediate container f70d6dd4dda2
    ---> 685cd05aa266
    Step 6/7 : ENV PATH $JAVA_HOME/bin:$PATH
    ---> Running in 934a8279744d
    Removing intermediate container 934a8279744d
    ---> 75f551548c7a
    Step 7/7 : CMD java -version
    ---> Running in 9ff68222bc64
    Removing intermediate container 9ff68222bc64
    ---> f1992f5f7b4c
    Successfully built f1992f5f7b4c
    Successfully tagged xiachaoyang/centos-java:latest

标记版本信息

xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker images
    REPOSITORY                TAG                 IMAGE ID            CREATED             SIZE
    xiachaoyang/centos-java   latest              f1992f5f7b4c        2 minutes ago       587MB
    xiachaoyang/centos-java   <none>              905af87b4a5e        10 hours ago        587MB
    centos                    latest              49f7960eb7e4        2 weeks ago         200MB
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker tag 905af87b4a5e xiachaoyang/centos-java:1.0
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker images
    REPOSITORY                TAG                 IMAGE ID            CREATED             SIZE
    xiachaoyang/centos-java   latest              f1992f5f7b4c        3 minutes ago       587MB
    xiachaoyang/centos-java   1.0                 905af87b4a5e        10 hours ago        587MB
    centos                    latest              49f7960eb7e4        2 weeks ago         200MB
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$

提交(运行中容器提交为镜像)

查看运行中容器

docker ps

将当前容器提交为一个新的镜像

docker commit [容器ID] xaichaoyang/centos-java

查看镜像

docker images

镜像删除

• • 
    
• 容器删除
  dokcer rm [容器ID]
• 容器批量删除
  ​​-f​​表示强制删除
  ​​ docker rm -f $(docker ps -a -q) docker rm -f `docker ps -a -q` ​​
• 镜像删除
  ​​docker rmi [镜像ID] ​​
• 批量删除
  ​​ docker rmi -f `docker images -a -q` ​​
• 
  

Dockerfile 踩坑

# 运行镜像测试
    xiazhaoyangdeMacBook-Pro:jdk-8u172-linux-x64 xiazhaoyang$ docker run --rm xiachaoyang/env-jdk java -version
    java version "1.8.0_172"
    Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
    Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)

查看容器列表信息

docker container ls -a

• 批量删除
  docker rm -f ​​docker ps -a -q​​

搭建Docker Registry（本地镜像仓库）

• 本地搭建
  
• 
  

下载并运行registry

-d : 表示后台启动该容器

-p : 表示对容器中应用程序暴露的端口号进行端口映射，冒号左边的端口(50000)为宿主机的端口，冒号右边的端口(5000)为容器内部需要报录的端口

-v : 数据卷选项，表示将宿主机的~/docker-registry 目录映射为容器的/tmp/registry

-restart：docker服务重启后总是重启此容器

xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker run -d -p 50000:5000 -v ~/docker-registry:/tmp/registry --name local_res registry
    5c08afe92712746db4fb48e02b5b274e205e7dce3cb38395846ca57b5d387c5e
    xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker ps
    CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                     NAMES
    5c08afe92712        registry            "/entrypoint.sh /etc…"   27 seconds ago      Up 26 seconds       0.0.0.0:50000->5000/tcp   determined_banach

访问​​http://127.0.0.1:5000/v2/_catalog?n=100​​查看仓库

> 下载web服务
docker run -it -p 8000:8080 --restart=always --name local-docker-res-web --link local-docker-res  -e REGISTRY_URL=http://local-docker-res:5000/v2 -e REGISTRY_NAME=localhost:5000 hyper/docker-registry-web

`8000:8080` 内置web服务是8080端口的，将内部8080端口映射到本机的8000端口上。
`REGISTRY_URL` 修改本地仓库域名
> 运行时遇到的问题
1. 8000：8000,内部8080启动失败：

- 查看运行中容器
docker ps
- 关闭容器
docker stop [容器ID]
- 容器搜索
docker container ls -a
- 删除容器
docker rm [容器ID]
- 再次运行web服务

2. 仓库名称写错
`I/O error on GET request for "http://registry-srv:5000/v2/_catalog?n=100":registry-srv; nested exception is java.net.UnknownHostException: registry-srv`
参考网上资料修改时未换成本地自定义仓库名local-docker-res
修改命令重新执行


- 操作时对于容器的状态还原

批量关闭容器
docker stop `docker ps -a -q`

批量删除容器
docker rm -f `docker ps -a -q`

删除镜像  
docker rmi -f [镜像ID]

本地仓库web服务

• 界面效果
  访问​​​http://127.0.0.1:8000/​​​查看仓库web界面

• 测试本地仓库推送

可能出现的push失败

$ docker push 127.0.0.1:5000/xiachaoyang/env-jdk
The push refers to a repository [127.0.0.1:5000/xiachoayang/env-jdk]
Get https://127.0.0.1:5000/v1/_ping: http: server gave HTTP response to HTTPS client

这是因为Docker在1.3.x之后默认docker registry使用的是https，为了解决这个问题，Linux中修改本地主机的docker启动配置文件，添加

--insecure-registry 127.0.0.1:5000

Docker for Mac中在图形化终端上修改如下，填写后“Apply&Restart”。

docker images
REPOSITORY                            TAG                 IMAGE ID            CREATED             SIZE
127.0.0.1:50000/xiachaoyang/env-jdk   latest              abe21e6640f3        2 days ago          587MB
xiachaoyang/env-jdk                   latest              abe21e6640f3        2 days ago          587MB
centos                                latest              49f7960eb7e4        3 weeks ago         200MB
registry                              latest              d1fd7d86a825        5 months ago        33.3MB
hyper/docker-registry-web             latest              0db5683824d8        20 months ago       599MB
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker tag abe21e6640f3  127.0.0.1:5000/xiachaoyang/env-jdk
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker push 127.0.0.1:5000/xiachaoyang/env-jdk
The push refers to repository [127.0.0.1:5000/xiachaoyang/env-jdk]
f65468761332: Pushed
5ed6bb2dd837: Pushing [===============>                                   ]  120.4MB/387.4MB
bcc97fbfc9e1: Pushing [=======================>                           ]  94.75MB/199.7MB

• 查看推送结果

• 删除镜像后测试本地仓库

docker images
REPOSITORY                  TAG                 IMAGE ID            CREATED             SIZE
centos                      latest              49f7960eb7e4        3 weeks ago         200MB
registry                    latest              d1fd7d86a825        5 months ago        33.3MB
hyper/docker-registry-web   latest              0db5683824d8        20 months ago       599MB
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker pull 127.0.0.1:5000/xiachaoyang/env-jdk
Using default tag: latest
latest: Pulling from xiachaoyang/env-jdk
7dc0dca2b151: Already exists
71ed27c83409: Pull complete
b7e1a9577e86: Pull complete
Digest: sha256:a7f0324eae38d9ce41389bccd43c92f3fa9d8a1a1dbe5ff52d6be978815fb267
Status: Downloaded newer image for 127.0.0.1:5000/xiachaoyang/env-jdk:latest

• 运行容器

xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker images
REPOSITORY                           TAG                 IMAGE ID            CREATED             SIZE
127.0.0.1:5000/xiachaoyang/env-jdk   latest              abe21e6640f3        2 days ago          587MB
centos                               latest              49f7960eb7e4        3 weeks ago         200MB
registry                             latest              d1fd7d86a825        5 months ago        33.3MB
hyper/docker-registry-web            latest              0db5683824d8        20 months ago       599MB
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker run --rm 127.0.0.1:5000/xiachaoyang/env-jdk java -version
java version "1.8.0_172"
Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$

docker restart 【容器ID】重新命令会保留挂参启动的配置信息

xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker ps
CONTAINER ID        IMAGE                       COMMAND             CREATED             STATUS              PORTS                    NAMES
9b17f2a0c10b        hyper/docker-registry-web   "start.sh"          23 hours ago        Up 23 hours         0.0.0.0:8000->8080/tcp   local-docker-res-web
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker container ls -a
CONTAINER ID        IMAGE                       COMMAND                  CREATED             STATUS                     PORTS                    NAMES
9b17f2a0c10b        hyper/docker-registry-web   "start.sh"               23 hours ago        Up 23 hours                0.0.0.0:8000->8080/tcp   local-docker-res-web
353ec8eb8c91        registry                    "/entrypoint.sh /etc…"   23 hours ago        Exited (2) 2 minutes ago                            local-docker-res
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker restart 353ec8eb8c91
353ec8eb8c91
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$ docker container ls -a
CONTAINER ID        IMAGE                       COMMAND                  CREATED             STATUS              PORTS                    NAMES
9b17f2a0c10b        hyper/docker-registry-web   "start.sh"               23 hours ago        Up 23 hours         0.0.0.0:8000->8080/tcp   local-docker-res-web
353ec8eb8c91        registry                    "/entrypoint.sh /etc…"   23 hours ago        Up 3 seconds        0.0.0.0:5000->5000/tcp   local-docker-res
xiazhaoyangdeMacBook-Pro:~ xiazhaoyang$

• 查看本地磁盘挂载中镜像
  若未找到本地镜像位置：需了解Docker在Mac中的数据卷挂载相关知识

镜像源配置

Mac下修改镜像源和阿里云镜像加速

• • 
    
• 阿里云注册和购买
• 产品和服务中选择容器镜像服务
  • 
    

​​Aliyun提供的Docker for Mac 安装包下载目录​​

如何配置镜像加速器

右键点击桌面顶栏的 docker 图标，选择 Preferences ，在 Daemon 标签（Docker 17.03 之前版本为 Advanced 标签）下的 Registry mirrors 列表中将​​https://xxxxx.mirror.aliyuncs.com​​加到”registry-mirrors”的数组里，点击 Apply & Restart按钮，等待Docker重启并应用配置的镜像加速器。

docker info

# http://hub-mirror.c.163.com/为网易docker镜像源

Insecure Registries:
 127.0.0.0/8
Registry Mirrors:
 http://hub-mirror.c.163.com/
 https://xxxx.mirror.aliyuncs.com/
Live Restore Enabled: false

配置后可以明显加快镜像拉取速度.

REFRENCES

1. 1. 
      
2. Dockerfile构建镜像
3. Docker私有仓库搭建
4. Dcoker数据卷挂载
   1. 
      

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