基于已有容器创建镜像

Dockerfile构建SSHD镜像

构建镜像

测试容器可以登陆

Dockerfile构建httpd镜像

构建镜像

测试容器

Dockerfile构建nginx镜像

构建镜像

概述：

Docker 镜像是Docker容器技术中的核心，也是应用打包构建发布的标准格式。一个完整的镜像可以支撑多个容器的运行，在Docker的整个使用过程中，进入一个已经定型的容器之后，就可以在容器中进行操作，最常见的操作就是在容器中安装应用服务。

如果想要把已经安装的服务容器进行迁移，就需要把环境以及部署的服务生成新的镜像。

程序打包方式：

打包成Tar包
打包成rpm包
打包成镜像

构建方式

1、基于已有的容器创建镜像

2、基于本地模板创建镜像

3、基于Dockerfile创建镜像

基于已有容器创建镜像

基于现有镜像创建主要使用 docker commit 命令，即把一个容器里面运行的程序以及该程序的运行环境打包起来生成新的镜像。

命令格式：

docker commit [选项] 容器ID/名称仓库名称:[标签]

常用选项：

-m 说明信息；
-a 作者信息；
-p 生成过程中停止容器的运行。

首先启动一个镜像，在容器里做相应的修改，然后将修改后的容器提交为新的镜像。需要记住该容器的ID号。

[root@localhost ~]# cat centos-7-x86_64.tar.gz |docker import - centos:7

sha256:790d0b6eb9de3d7ba8df7d91a54d236b381f4800ac751205a1fb6b77cc0c7efd

[root@localhost sshd]# docker run -it centos:7 /bin/bash

WARNING: IPv4 forwarding is disabled. Networking will not work.

[root@d80919f3c00c /]# ls

bin   dev fastboot lib    lost+found mnt proc run   srv tmp var

boot etc home      lib64 media       opt root sbin sys usr

[root@d80919f3c00c /]# touch lifenghai                  创建测试文件

[root@d80919f3c00c /]# ls

bin   dev fastboot lib    lifenghai   media opt   root sbin sys usr

boot etc home      lib64 lost+found mnt    proc run   srv   tmp var

[root@d80919f3c00c /]# exit

exit

[root@localhost sshd]# docker commit -m "crushlinux test images" -a "crushlinux" d80919f3c00c centos7:ddd

该命令的意思是将容器ID为d80919f3c00c 的容器的更改保存为名为"centos7:new"的新镜像，并指定了提交消息为"crushlinux test images"，作者为"crushlinux"。

sha256:595d590702ffc0ca7e23f11f552266c924261c5966f7634de96ba7dfe6a547c3

[root@localhost sshd]# docker images centos7:ddd

REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

centos7             ddd                 595d590702ff        25 seconds ago      589 MB

[root@localhost sshd]# docker run -it centos7:ddd /bin/bash

WARNING: IPv4 forwarding is disabled. Networking will not work.

[root@14ad9a706c54 /]# ls

bin   dev fastboot lib    lifenghai   media opt   root sbin sys usr

boot etc home      lib64 lost+found mnt    proc run   srv   tmp var

这是一个Docker命令，用于将一个容器的更改保存为新的镜像。具体解释如下：

docker commit：Docker命令，用于提交容器的更改。
-m "crushlinux test images"：使用-m参数指定提交的消息，这里是"crushlinux test images"。
-a "crushlinux"：使用-a参数指定作者，这里是"crushlinux"。
d281f905fb30：容器的ID或名称，表示要提交更改的容器。
centos7:new：新镜像的名称和标签，这里是"centos7:new"。

因此，该命令的意思是将容器ID为d281f905fb30的容器的更改保存为名为"centos7:new"的新镜像，并指定了提交消息为"crushlinux test images"，作者为"crushlinux"。

Dockerfile构建SSHD镜像

关闭防火墙规则

iptables -F
setenforce 0
systemctl stop firewalld

修改配置

[root@localhost ~]# cat /etc/resolv.conf

# Generated by NetworkManager

nameserver 8.8.8.8

search localdomain

创建备用目录

[root@localhost ~]# mkdir sshd

获取密钥

[root@localhost ~]# ssh-keygen

Generating public/private rsa key pair.

Enter file in which to save the key (/root/.ssh/id_rsa):

Created directory '/root/.ssh'.

Enter passphrase (empty for no passphrase):

Enter same passphrase again:

Your identification has been saved in /root/.ssh/id_rsa.

Your public key has been saved in /root/.ssh/id_rsa.pub.

The key fingerprint is:

SHA256:6j2zE3PzgNt4sQdpeR0BUSO4NCrtnissqN4xHJZVoLE root@localhost.localdomain

The key's randomart image is:

+---[RSA 2048]----+

|   . ...   .++o |

|    + .   + ... |

|   E . . o o   . |

|    o . o .   . |

|   +   oS. o . . |

| o . .= X . . |

|   = ... X O     |

| o +.o.O + o    |

|oo . ...+B .     |

+----[SHA256]-----+

拷贝文件

[root@localhost ~]# cp .ssh/id_rsa.pub sshd/

[root@localhost ~]# cd sshd/

[root@localhost ~]# ll

总用量 591996

-rw-------. 1 root root      1415 7月 31 19:02 anaconda-ks.cfg

-rw-r--r--. 1 root root 221692852 7月 17 2020 centos-7-x86_64.tar.gz

-rw-r--r--. 1 root root 238594048 7月 31 14:26 centos-exp

-rw-------. 1 root root 145905152 7月 31 14:36 nginx-images

drwxr-xr-x. 2 root root        47 8月   2 13:57 sshd

导入镜像

[root@localhost ~]# cat centos-7-x86_64.tar.gz |docker import - centos:7

sha256:790d0b6eb9de3d7ba8df7d91a54d236b381f4800ac751205a1fb6b77cc0c7efd

编写Dockerfile文件

[root@localhost sshd]# vim Dockerfile

#基于的基础镜像

FROM centos:7

#镜像作者信息

MAINTAINER Crushlinux <crushlinux@163.com>

#镜像执行的命令

RUN yum -y install openssh-server net-tools openssh-devel lsof telnet

RUN sed -i 's/UsePAM yes/UsePAM no/g' /etc/ssh/sshd_config

RUN ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key

RUN ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key

ADD id_rsa.pub /root/.ssh/authorized_keys

#定义时区

RUN ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime

#开启 22 端口

EXPOSE 22

#启动容器时执行指令

CMD ["/usr/sbin/sshd" , "-D"]

~

~

重启

[root@localhost sshd]# systemctl restart network

[root@localhost sshd]# systemctl restart docker

构建镜像

[root@localhost sshd]#  docker build -t sshd:new .Sending build context to Docker daemon 3.584 kBStep 1/9 : FROM centos:7---> 790d0b6eb9deStep 2/9 : MAINTAINER Crushlinux <crushlinux@163.com>---> Using cache---> f5d4ad40d1dfStep 3/9 : RUN yum -y install openssh-server net-tools openssh-devel lsof telnet---> Running in bdb9cc0dfb6cLoaded plugins: fastestmirrorDetermining fastest mirrors* base: mirrors.bfsu.edu.cn* extras: mirrors.ustc.edu.cn* updates: mirrors.ustc.edu.cnNo package openssh-devel available.Resolving Dependencies--> Running transaction check---> Package lsof.x86_64 0:4.87-4.el7 will be updated---> Package lsof.x86_64 0:4.87-6.el7 will be an update---> Package net-tools.x86_64 0:2.0-0.25.20131004git.el7 will be installed---> Package openssh-server.x86_64 0:6.6.1p1-25.el7_2 will be updated---> Package openssh-server.x86_64 0:7.4p1-22.el7_9 will be an update--> Processing Dependency: openssh = 7.4p1-22.el7_9 for package: openssh-server-7.4p1-22.el7_9.x86_64--> Processing Dependency: libcrypto.so.10(OPENSSL_1.0.2)(64bit) for package: openssh-server-7.4p1-22.el7_9.x86_64---> Package telnet.x86_64 1:0.17-59.el7 will be updated---> Package telnet.x86_64 1:0.17-66.el7 will be an update--> Running transaction check---> Package openssh.x86_64 0:6.6.1p1-25.el7_2 will be updated--> Processing Dependency: openssh = 6.6.1p1-25.el7_2 for package: openssh-clients-6.6.1p1-25.el7_2.x86_64---> Package openssh.x86_64 0:7.4p1-22.el7_9 will be an update---> Package openssl-libs.x86_64 1:1.0.1e-51.el7_2.5 will be updated--> Processing Dependency: openssl-libs(x86-64) = 1:1.0.1e-51.el7_2.5 for package: 1:openssl-1.0.1e-51.el7_2.5.x86_64---> Package openssl-libs.x86_64 1:1.0.2k-26.el7_9 will be an update--> Running transaction check---> Package openssh-clients.x86_64 0:6.6.1p1-25.el7_2 will be updated---> Package openssh-clients.x86_64 0:7.4p1-22.el7_9 will be an update---> Package openssl.x86_64 1:1.0.1e-51.el7_2.5 will be updated---> Package openssl.x86_64 1:1.0.2k-26.el7_9 will be an update--> Finished Dependency ResolutionDependencies Resolved================================================================================Package             Arch       Version                       Repository   Size================================================================================Installing:net-tools           x86_64     2.0-0.25.20131004git.el7      base        306 kUpdating:lsof                x86_64     4.87-6.el7                    base        331 kopenssh-server      x86_64     7.4p1-22.el7_9                updates     459 ktelnet              x86_64     1:0.17-66.el7                 updates      64 kUpdating for dependencies:openssh             x86_64     7.4p1-22.el7_9                updates     510 kopenssh-clients     x86_64     7.4p1-22.el7_9                updates     655 kopenssl             x86_64     1:1.0.2k-26.el7_9             updates     494 kopenssl-libs        x86_64     1:1.0.2k-26.el7_9             updates     1.2 MTransaction Summary================================================================================Install  1 PackageUpgrade  3 Packages (+4 Dependent packages)Total download size: 4.0 MDownloading packages:Delta RPMs disabled because /usr/bin/applydeltarpm not installed.warning: /var/cache/yum/x86_64/7/base/packages/lsof-4.87-6.el7.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID f4a80eb5: NOKEYPublic key for lsof-4.87-6.el7.x86_64.rpm is not installedPublic key for openssh-server-7.4p1-22.el7_9.x86_64.rpm is not installedImporting GPG key 0xF4A80EB5:Userid     : "CentOS-7 Key (CentOS 7 Official Signing Key) <security@centos.org>"Fingerprint: 6341 ab27 53d7 8a78 a7c2 7bb1 24c6 a8a7 f4a8 0eb5Package    : centos-release-7-2.1511.el7.centos.2.10.x86_64 (installed)From       : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7--------------------------------------------------------------------------------Total                                              622 kB/s | 4.0 MB  00:06     Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7Running transaction checkRunning transaction testTransaction test succeededRunning transactionUpdating   : 1:openssl-libs-1.0.2k-26.el7_9.x86_64                       1/15Updating   : openssh-7.4p1-22.el7_9.x86_64                               2/15Updating   : openssh-server-7.4p1-22.el7_9.x86_64                        3/15warning: /etc/ssh/sshd_config created as /etc/ssh/sshd_config.rpmnewUpdating   : openssh-clients-7.4p1-22.el7_9.x86_64                       4/15Updating   : 1:openssl-1.0.2k-26.el7_9.x86_64                            5/15Installing : net-tools-2.0-0.25.20131004git.el7.x86_64                   6/15Updating   : lsof-4.87-6.el7.x86_64                                      7/15Updating   : 1:telnet-0.17-66.el7.x86_64                                 8/15Cleanup    : openssh-clients-6.6.1p1-25.el7_2.x86_64                     9/15Cleanup    : openssh-server-6.6.1p1-25.el7_2.x86_64                     10/15Cleanup    : openssh-6.6.1p1-25.el7_2.x86_64                            11/15Cleanup    : 1:openssl-1.0.1e-51.el7_2.5.x86_64                         12/15Cleanup    : 1:openssl-libs-1.0.1e-51.el7_2.5.x86_64                    13/15Cleanup    : lsof-4.87-4.el7.x86_64                                     14/15Cleanup    : 1:telnet-0.17-59.el7.x86_64                                15/15Verifying  : 1:telnet-0.17-66.el7.x86_64                                 1/15Verifying  : openssh-server-7.4p1-22.el7_9.x86_64                        2/15Verifying  : 1:openssl-libs-1.0.2k-26.el7_9.x86_64                       3/15Verifying  : lsof-4.87-6.el7.x86_64                                      4/15Verifying  : net-tools-2.0-0.25.20131004git.el7.x86_64                   5/15Verifying  : openssh-clients-7.4p1-22.el7_9.x86_64                       6/15Verifying  : openssh-7.4p1-22.el7_9.x86_64                               7/15Verifying  : 1:openssl-1.0.2k-26.el7_9.x86_64                            8/15Verifying  : 1:telnet-0.17-59.el7.x86_64                                 9/15Verifying  : openssh-6.6.1p1-25.el7_2.x86_64                            10/15Verifying  : 1:openssl-1.0.1e-51.el7_2.5.x86_64                         11/15Verifying  : openssh-server-6.6.1p1-25.el7_2.x86_64                     12/15Verifying  : openssh-clients-6.6.1p1-25.el7_2.x86_64                    13/15Verifying  : lsof-4.87-4.el7.x86_64                                     14/15Verifying  : 1:openssl-libs-1.0.1e-51.el7_2.5.x86_64                    15/15Installed:net-tools.x86_64 0:2.0-0.25.20131004git.el7                                   Updated:lsof.x86_64 0:4.87-6.el7          openssh-server.x86_64 0:7.4p1-22.el7_9      telnet.x86_64 1:0.17-66.el7      Dependency Updated:openssh.x86_64 0:7.4p1-22.el7_9     openssh-clients.x86_64 0:7.4p1-22.el7_9   openssl.x86_64 1:1.0.2k-26.el7_9    openssl-libs.x86_64 1:1.0.2k-26.el7_9     Complete!---> 4d1711b1891cRemoving intermediate container bdb9cc0dfb6cStep 4/9 : RUN sed -i 's/UsePAM yes/UsePAM no/g' /etc/ssh/sshd_config---> Running in c6bcc01f445e---> 20b01ccf2a71Removing intermediate container c6bcc01f445eStep 5/9 : RUN ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key---> Running in 8d573e2d3e45Generating public/private rsa key pair.Your identification has been saved in /etc/ssh/ssh_host_rsa_key.Your public key has been saved in /etc/ssh/ssh_host_rsa_key.pub.The key fingerprint is:SHA256:Q9t9zoZ4iE/eCmeKuyUqmUt1IRvPo34wrWN5wbo8ypE root@bdb9cc0dfb6cThe key's randomart image is:+---[RSA 2048]----+|                 ||                 ||    o . .        ||     * o o .     ||    oo= S . . .  ||   ooo+. o o =   ||  Eo.*..+ * o +  || o++B.o+ O o .   ||  +==*+o. +..    |+----[SHA256]-----+Enter passphrase (empty for no passphrase): Enter same passphrase again:  ---> 14dd7eb2256fRemoving intermediate container 8d573e2d3e45Step 6/9 : ADD id_rsa.pub /root/.ssh/authorized_keys---> 99984eb1e50eRemoving intermediate container 369022575e01Step 7/9 : RUN ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime---> Running in b0056bbc027e---> 950f0c260a79Removing intermediate container b0056bbc027eStep 8/9 : EXPOSE 22---> Running in 190b29e65718---> c6a476cb31b4Removing intermediate container 190b29e65718Step 9/9 : CMD /usr/sbin/sshd -D---> Running in 0b76956add3a---> a600eb2f7badRemoving intermediate container 0b76956add3aSuccessfully built a600eb2f7bad

测试容器可以登陆

[root@localhost sshd]# docker images sshd:new

REPOSITORY TAG IMAGE ID CREATED SIZE

sshd new a600eb2f7bad 3 minutes ago 821 MB

[root@localhost sshd]# docker run -d -p 2222:22 --name sshd-test --restart=always sshd:new

61a2bbb409288f6d1e0c95dfe8ef9b732b77bcd35129972700d181fefa08631e

[root@localhost sshd]# ssh localhost -p 2222

The authenticity of host '[localhost]:2222 ([::1]:2222)' can't be established.

RSA key fingerprint is SHA256:Q9t9zoZ4iE/eCmeKuyUqmUt1IRvPo34wrWN5wbo8ypE.

RSA key fingerprint is MD5:1e:97:2c:02:4d:35:1e:3f:68:a0:30:9c:cc:53:a2:cf.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added '[localhost]:2222' (RSA) to the list of known hosts.

[root@61a2bbb40928 ~]#

[root@61a2bbb40928 ~]# exit

登出

Connection to localhost closed.

Dockerfile构建httpd镜像

创建工作目录

[root@localhost ~]# mkdir httpd

[root@localhost ~]# cd httpd/

编写Dockerfile文件

[root@localhost httpd]# vim Dockerfile

[root@localhost httpd]# cat Dockerfile

FROM centos:7

MAINTAINER hhh <hhh@163.com>

RUN yum -y install httpd

RUN echo "crushlinux" >/var/www/html/index.html

RUN ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime

EXPOSE 80

CMD ["httpd","-DFOREGROUND"]

构建镜像

[root@localhost httpd]# docker build -t httpd:new .

Sending build context to Docker daemon 2.048 kB

Step 1/7 : FROM centos:7

---> 790d0b6eb9de

Step 2/7 : MAINTAINER hhh <hhh@163.com>

---> Using cache

---> 25eef094ceba

Step 3/7 : RUN yum -y install httpd

---> Running in 8324e3b4b5c7

Loaded plugins: fastestmirror

Determining fastest mirrors

* base: mirrors.bfsu.edu.cn

* extras: mirrors.bfsu.edu.cn

* updates: mirrors.bfsu.edu.cn

Resolving Dependencies

--> Running transaction check

---> Package httpd.x86_64 0:2.4.6-40.el7.centos.1 will be updated

---> Package httpd.x86_64 0:2.4.6-99.el7.centos.1 will be an update

--> Processing Dependency: httpd-tools = 2.4.6-99.el7.centos.1 for package: httpd-2.4.6-99.el7.centos.1.

--> Running transaction check

---> Package httpd-tools.x86_64 0:2.4.6-40.el7.centos.1 will be updated

---> Package httpd-tools.x86_64 0:2.4.6-99.el7.centos.1 will be an update

--> Finished Dependency Resolution

Dependencies Resolved

================================================================================

Package           Arch         Version                     Repository     Size

================================================================================

Updating:

httpd             x86_64       2.4.6-99.el7.centos.1       updates       2.7 M

Updating for dependencies:

httpd-tools       x86_64       2.4.6-99.el7.centos.1       updates        94 k

Transaction Summary

================================================================================

Upgrade 1 Package (+1 Dependent package)

Total download size: 2.8 M

Downloading packages:

Delta RPMs disabled because /usr/bin/applydeltarpm not installed.

Public key for httpd-tools-2.4.6-99.el7.centos.1.x86_64.rpm is not installed

warning: /var/cache/yum/x86_64/7/updates/packages/httpd-tools-2.4.6-99.el7.centos.1.x86_64.rpm: Header V

--------------------------------------------------------------------------------

Total                                              1.6 MB/s | 2.8 MB 00:01

Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

Importing GPG key 0xF4A80EB5:

Userid     : "CentOS-7 Key (CentOS 7 Official Signing Key) <security@centos.org>"

Fingerprint: 6341 ab27 53d7 8a78 a7c2 7bb1 24c6 a8a7 f4a8 0eb5

Package    : centos-release-7-2.1511.el7.centos.2.10.x86_64 (installed)

From       : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

Running transaction check

Running transaction test

Transaction test succeeded

Running transaction

  Updating   : httpd-tools-2.4.6-99.el7.centos.1.x86_64                     1/4

  Updating   : httpd-2.4.6-99.el7.centos.1.x86_64                           2/4

  Cleanup    : httpd-2.4.6-40.el7.centos.1.x86_64                           3/4

  Cleanup    : httpd-tools-2.4.6-40.el7.centos.1.x86_64                     4/4

  Verifying : httpd-2.4.6-99.el7.centos.1.x86_64                           1/4

  Verifying : httpd-tools-2.4.6-99.el7.centos.1.x86_64                     2/4

  Verifying : httpd-2.4.6-40.el7.centos.1.x86_64                           3/4

  Verifying : httpd-tools-2.4.6-40.el7.centos.1.x86_64                     4/4

Updated:

  httpd.x86_64 0:2.4.6-99.el7.centos.1

Dependency Updated:

  httpd-tools.x86_64 0:2.4.6-99.el7.centos.1

Complete!

---> 2214fb4006c9

Removing intermediate container 8324e3b4b5c7

Step 4/7 : RUN echo "crushlinux" >/var/www/html/index.html

---> Running in badb364c7e55

---> a9b433c350e4

Removing intermediate container badb364c7e55

Step 5/7 : RUN ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime

---> Running in d0081e48aa43

---> ffaf678f3cfc

Removing intermediate container d0081e48aa43

Step 6/7 : EXPOSE 80

---> Running in 3bd620f29826

---> 89d665eda838

Removing intermediate container 3bd620f29826

Step 7/7 : CMD httpd -DFOREGROUND

---> Running in 2dea705ece43

---> 7f5e5dc62d40

Removing intermediate container 2dea705ece43

Successfully built 7f5e5dc62d40

查看

[root@localhost httpd]# docker images httpd

REPOSITORY TAG IMAGE ID CREATED SIZE

httpd new 7f5e5dc62d40 2 minutes ago 819 MB

测试容器

[root@localhost httpd]# docker run -d -p 8080:80 --name httpd-test --restart=always httpd:new

90bc8641fbefdf722c5d5842931d776bcbef0a6766c66f3fbc92d966d5752460

Dockerfile构建nginx镜像

建立工作目录

[root@localhost ~]# mkdir nginx

[root@localhost ~]# cd nginx

编写Dockerfile文件

[root@localhost nginx]# vim run.sh

[root@localhost nginx]# cat run.sh

#!/bin/bash

/usr/local/nginx/sbin/nginx

[root@localhost nginx]# cat Dockerfile

#基于的基础镜像

FROM centos:7

#镜像作者信息

MAINTAINER hhh <hhh@163.com>

#安装相关依赖包

RUN yum install -y wget proc-devel net-tools gcc zlib zlib-devel make openssl-devel

#下载并解压nginx源码包

RUN wget http://nginx.org/download/nginx-1.19.0.tar.gz && tar zxf nginx-1.19.0.tar.gz

#编译安装nginx

RUN cd nginx-1.19.0 && ./configure --prefix=/usr/local/nginx && make && make install

#开启 80 和 443 端口

EXPOSE 80

#修改 Nginx 配置文件,以非 daemon 方式启动

RUN echo "daemon off;">>/usr/local/nginx/conf/nginx.conf

#定义时区

RUN ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime

#复制服务启动脚本并设置权限

ADD run.sh /run.sh

RUN chmod 775 /run.sh

#启动容器时执行脚本

CMD ["/run.sh"]