Dockerfile详解【2】 1. Base镜像的说明 docker Hub上99%的镜像都是通过base镜像中安装和配置需要的软件构建出来的。
2. 自定义mycentos镜像 2.1 目标:
登陆后的默认路径
vim编辑器
2.2 进入mydocker目录创建DockerFile，文件编写 1 2 3 4 [root@localhost centos]# pwd /usr/local/docker/docker_file/centos [root@localhost centos]# touch Dockerfile [root@localhost centos]# vim Dockerfile
向Dockerfile里面写入内容
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 FROM centosMAINTAINER Tom<Tom@qq.com>ENV MYPATH /usr/localWORKDIR ${MYPATH} RUN yum -y install vim EXPOSE 80 CMD echo ${MYPATH} CMD echo "success, finished!" CMD /bin/bash
2.3 使用docker build命令构建镜像 1 [root@localhost centos]# docker build -t mycentos01:2.0 .
container id: 814f0d94c86b, image id: e91b1474c962
output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 Sending build context to Docker daemon 2.048 kB Step 1/9 : FROM centos ---> 0d120b6ccaa8 Step 2/9 : MAINTAINER Tom<Tom@qq.com> ---> Running in 814f0d94c86b ---> e91b1474c962 Removing intermediate container 814f0d94c86b Step 3/9 : ENV MYPATH /usr/local ---> Running in 96525b6c63e9 ---> bacb4c16c1f0 Removing intermediate container 96525b6c63e9 Step 4/9 : WORKDIR ${MYPATH} ---> d622aa686883 Removing intermediate container a9cf9ea40f1f Step 5/9 : RUN yum -y install vim ---> Running in bd65d6cdd4e1 CentOS-8 - AppStream 3.4 MB/s | 5.8 MB 00:01 CentOS-8 - Base 1.1 MB/s | 2.2 MB 00:02 CentOS-8 - Extras 10 kB/s | 8.6 kB 00:00 Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: vim-enhanced x86_64 2:8.0.1763-13.el8 AppStream 1.4 M Installing dependencies: gpm-libs x86_64 1.20.7-15.el8 AppStream 39 k vim-common x86_64 2:8.0.1763-13.el8 AppStream 6.3 M vim-filesystem noarch 2:8.0.1763-13.el8 AppStream 48 k which x86_64 2.21-12.el8 BaseOS 49 k Transaction Summary ================================================================================ Install 5 Packages Total download size: 7.8 M Installed size: 31 M Downloading Packages: (1/5): gpm-libs-1.20.7-15.el8.x86_64.rpm 623 kB/s | 39 kB 00:00 (2/5): vim-filesystem-8.0.1763-13.el8.noarch.rp 848 kB/s | 48 kB 00:00 (3/5): which-2.21-12.el8.x86_64.rpm 332 kB/s | 49 kB 00:00 (4/5): vim-enhanced-8.0.1763-13.el8.x86_64.rpm 411 kB/s | 1.4 MB 00:03 (5/5): vim-common-8.0.1763-13.el8.x86_64.rpm 398 kB/s | 6.3 MB 00:16 -------------------------------------------------------------------------------- Total 430 kB/s | 7.8 MB 00:18 warning: /var/cache/dnf/AppStream-02e86d1c976ab532/packages/gpm-libs-1.20.7-15.e l8.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID 8483c65d: NOKEY CentOS-8 - AppStream 17 kB/s | 1.6 kB 00:00 Importing GPG key 0x8483C65D: Userid : "CentOS (CentOS Official Signing Key) <security@centos.org>" Fingerprint: 99DB 70FA E1D7 CE22 7FB6 4882 05B5 55B3 8483 C65D From : /etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial Key imported successfully Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : which-2.21-12.el8.x86_64 1/5 Installing : vim-filesystem-2:8.0.1763-13.el8.noarch 2/5 Installing : vim-common-2:8.0.1763-13.el8.x86_64 3/5 Installing : gpm-libs-1.20.7-15.el8.x86_64 4/5 Running scriptlet: gpm-libs-1.20.7-15.el8.x86_64 4/5 Installing : vim-enhanced-2:8.0.1763-13.el8.x86_64 5/5 Running scriptlet: vim-enhanced-2:8.0.1763-13.el8.x86_64 5/5 Running scriptlet: vim-common-2:8.0.1763-13.el8.x86_64 5/5 Verifying : gpm-libs-1.20.7-15.el8.x86_64 1/5 Verifying : vim-common-2:8.0.1763-13.el8.x86_64 2/5 Verifying : vim-enhanced-2:8.0.1763-13.el8.x86_64 3/5 Verifying : vim-filesystem-2:8.0.1763-13.el8.noarch 4/5 Verifying : which-2.21-12.el8.x86_64 5/5 Installed: gpm-libs-1.20.7-15.el8.x86_64 vim-common-2:8.0.1763-13.el8.x86_64 vim-enhanced-2:8.0.1763-13.el8.x86_64 vim-filesystem-2:8.0.1763-13.el8.noarch which-2.21-12.el8.x86_64 Complete! ---> 160bf8d94eca Removing intermediate container bd65d6cdd4e1 Step 6/9 : EXPOSE 80 ---> Running in 5c4ba5591c52 ---> c12aa2483683 Removing intermediate container 5c4ba5591c52 Step 7/9 : CMD echo ${MYPATH} ---> Running in 0b9240516a40 ---> b91d27669bd4 Removing intermediate container 0b9240516a40 Step 8/9 : CMD echo "success, finished!" ---> Running in 99a9807164f3 ---> 384b4018892b Removing intermediate container 99a9807164f3 Step 9/9 : CMD /bin/bash ---> Running in 89d99aa2efd7 ---> f503701c7737 Removing intermediate container 89d99aa2efd7 Successfully built f503701c7737
1 2 3 [root@localhost centos]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE mycentos01 2.0 f503701c7737 22 minutes ago 272 MB
2.4 使用docker run命令运行 1 [root@localhost centos]# docker run -it mycentos01:2.0
2.5 列出镜像的变更历史 docker history 镜像名:TAG
1 [root@localhost centos]# docker history mycentos01:2.0
1 2 3 4 5 6 7 8 9 10 11 12 IMAGE CREATED CREATED BY SIZE COMMENT f503701c7737 23 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "/b... 0 B 384b4018892b 23 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "ec... 0 B b91d27669bd4 23 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "ec... 0 B c12aa2483683 23 minutes ago /bin/sh -c #(nop) EXPOSE 80/tcp 0 B 160bf8d94eca 23 minutes ago /bin/sh -c yum -y install vim 57.3 MB d622aa686883 24 minutes ago /bin/sh -c #(nop) WORKDIR /usr/local 0 B bacb4c16c1f0 24 minutes ago /bin/sh -c #(nop) ENV MYPATH=/usr/local 0 B e91b1474c962 24 minutes ago /bin/sh -c #(nop) MAINTAINER Tom<Tom@qq.com> 0 B 0d120b6ccaa8 3 months ago /bin/sh -c #(nop) CMD ["/bin/bash"] 0 B <missing> 3 months ago /bin/sh -c #(nop) LABEL org.label-schema.... 0 B <missing> 3 months ago /bin/sh -c #(nop) ADD file:538afc0c5c964ce... 215 MB