每天一点基础K8S--dockerfile练习

标签：14 -- root --- Step test K8S dockerfile
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# dockerfile文件
[11-14 15:39:27 huawei root ~/dockerfile] # ls -l 
total 8
-rw-r--r-- 1 root root 579 Nov 14 15:25 dockerfile
-rw-r--r-- 1 root root  20 Nov 14 15:26 test_copy.file


[11-14 15:39:37 huawei root ~/dockerfile] # cat dockerfile  -n
     1  FROM centos:latest
     2  MAINTAINER huan
     3  EXPOSE 8888
     4  VOLUME /test_dockerfile_datavolume
     5  RUN touch test_run_command
     6  WORKDIR /home
     7  RUN touch test_run_command
     8  CMD touch test_cmd_command
     9  COPY test_copy.file /var/log/test_copy.file
    10  ADD https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo /etc/yum.repos.d/test.repo
    11  ARG author=huanhuan
    12  LABEL mathor="this is a image build from centos " author=$author
    13  ENV testuser="test"
    14  CMD useradd test
    15  USER test
    16  CMD touch test_file_user
    17  USER root
    18  ONBUILD CMD touch test_onbuild_command
    19  ENTRYPOINT ["/bin/bash","-c"]
    20  CMD tail -F /var/log/aaaa



#构建镜像

[11-14 15:27:35 huawei root ~/dockerfile] # docker build -t "test:dockerfile" .
Sending build context to Docker daemon 3.584 kB
Step 1/20 : FROM centos:latest
 ---> 5d0da3dc9764
Step 2/20 : MAINTAINER huan
 ---> Running in 63e438f5166a
 ---> 32c4be9a9fd8
Removing intermediate container 63e438f5166a
Step 3/20 : EXPOSE 8888
 ---> Running in dc87e3719a16
 ---> 5c7730fd7cfd
Removing intermediate container dc87e3719a16
Step 4/20 : VOLUME /test_dockerfile_datavolume
 ---> Running in 9e17ec2197b7
 ---> f2ebf930107b
Removing intermediate container 9e17ec2197b7
Step 5/20 : RUN touch test_run_command
 ---> Running in eefedf0ed2e2


 ---> c2ffd2228bab
Removing intermediate container eefedf0ed2e2
Step 6/20 : WORKDIR /home
 ---> 749b0d41cbcc
Removing intermediate container 7758e784a08a
Step 7/20 : RUN touch test_run_command
 ---> Running in 51be6bbd145b


 ---> 3a1fbbde10e9
Removing intermediate container 51be6bbd145b
Step 8/20 : CMD touch test_cmd_command
 ---> Running in cbc4fc33ebb3
 ---> 3558407cd1d7
Removing intermediate container cbc4fc33ebb3
Step 9/20 : COPY test_copy.file /var/log/test_copy.file
 ---> 3228664373fb
Removing intermediate container eb4ff5609d6e
Step 10/20 : ADD https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo /etc/yum.repos.d/test.repo
Downloading [==================================================>] 2.495 kB/2.495 kB


 ---> d9febacae0b5
Removing intermediate container eae94ab84663
Step 11/20 : ARG author=huanhuan
 ---> Running in a9c1daca30a3
 ---> 0d29df131ab3
Removing intermediate container a9c1daca30a3
Step 12/20 : LABEL mathor "this is a image build from centos " author $author
 ---> Running in 50bc1aedf70e
 ---> 810f42a8b862
Removing intermediate container 50bc1aedf70e
Step 13/20 : ENV testuser "test"
 ---> Running in 3bd4d21aa3e6
 ---> d19d5520022c
Removing intermediate container 3bd4d21aa3e6
Step 14/20 : CMD useradd $testuser
 ---> Running in 375b79119b9a
 ---> 733c1deb294e
Removing intermediate container 375b79119b9a
Step 15/20 : USER $testuser
 ---> Running in 2d81f0273840
 ---> 769b1ba02426
Removing intermediate container 2d81f0273840
Step 16/20 : CMD touch test_file_user
 ---> Running in f8ba03aa4f9d
 ---> f173e21b2a82
Removing intermediate container f8ba03aa4f9d
Step 17/20 : USER root
 ---> Running in 851381e61a53
 ---> 579755bf00c2
Removing intermediate container 851381e61a53
Step 18/20 : ONBUILD CMD touch 
 ---> Running in 828d41facfb7
 ---> 85d8171fc6be
Removing intermediate container 828d41facfb7
Step 19/20 : ENTRYPOINT /bin/bash -c
 ---> Running in 6618388998d5
 ---> ff0e3337b2bb
Removing intermediate container 6618388998d5
Step 20/20 : CMD tail -F /var/log/aaaa
 ---> Running in 0434c3fbf757
 ---> c5d4667d2e8a
Removing intermediate container 0434c3fbf757
Successfully built c5d4667d2e8a
You have mail in /var/spool/mail/root


# 查看构建的镜像
[11-14 16:17:22 huawei root ~/dockerfile] # docker images  |  grep dockerfile
test                                              dockerfile           c5d4667d2e8a        49 minutes ago      231 MB

[11-14 16:18:55 huawei root ~/dockerfile] # docker image inspect test:dockerfile 
[
    {
        "Id": "sha256:c5d4667d2e8ae110d4a3d2376af548e0ec6373cbd0b67fbc975df31c1929fe2b",
        "RepoTags": [
            "test:dockerfile"
        ],
        "RepoDigests": [],
        "Parent": "sha256:ff0e3337b2bb0c4598699b124429da857b264a5cba5b6c5fddde0dafe6a2b0d7",
        "Comment": "",
        "Created": "2022-11-14T07:27:49.566318799Z",
        "Container": "0434c3fbf7576343367c0596a27df517441f542d07aba338ba2b8eb530c2473a",
        "ContainerConfig": {
            "Hostname": "63e438f5166a",
            "Domainname": "",
            "User": "root",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "ExposedPorts": {
                "8888/tcp": {}    # expose 端口
            },
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "testuser=test"        # env变量
            ],
            "Cmd": [
                "/bin/sh",
                "-c",
                "#(nop) ",
                "CMD [\"/bin/sh\" \"-c\" \"tail -F /var/log/aaaa\"]”    # CMD
            ],
            "ArgsEscaped": true,
            "Image": "sha256:ff0e3337b2bb0c4598699b124429da857b264a5cba5b6c5fddde0dafe6a2b0d7",
            "Volumes": {
                "/test_dockerfile_datavolume": {}        # volume
            },
            "WorkingDir": "/home",            # workdir
            "Entrypoint": [
                "/bin/bash",                # unbuild
                "-c"
            ],
            "OnBuild": [
                “CMD touch test_onbuild_command"        # onbiuld
            ],
            "Labels": {
                "author": "huanhuan”,        # label 调用arg
                "mathor": "this is a image build from centos “,    # label
                "org.label-schema.build-date": "20210915",
                "org.label-schema.license": "GPLv2",
                "org.label-schema.name": "CentOS Base Image",
                "org.label-schema.schema-version": "1.0",
                "org.label-schema.vendor": "CentOS"
            }
        },
        "DockerVersion": "1.13.1",
        "Author": "huan",
        "Config": {
            "Hostname": "63e438f5166a",
            "Domainname": "",
            "User": "root",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "ExposedPorts": {
                "8888/tcp": {}
            },
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "testuser=test"
            ],
            "Cmd": [
                "/bin/sh",
                "-c",
                "tail -F /var/log/aaaa"
            ],
            "ArgsEscaped": true,
            "Image": "sha256:ff0e3337b2bb0c4598699b124429da857b264a5cba5b6c5fddde0dafe6a2b0d7",
            "Volumes": {
                "/test_dockerfile_datavolume": {}
            },
            "WorkingDir": "/home",
            "Entrypoint": [
                "/bin/bash",
                "-c"
            ],
            "OnBuild": [
                “CMD touch test_onbuild_command"
            ],
            "Labels": {
                "author": "huanhuan”,        # 调用arg变量；
                "mathor": "this is a image build from centos “,    # 这里与dockerfile中的label对应
                "org.label-schema.build-date": "20210915",
                "org.label-schema.license": "GPLv2",
                "org.label-schema.name": "CentOS Base Image",
                "org.label-schema.schema-version": "1.0",
                "org.label-schema.vendor": "CentOS"
            }
        },
        "Architecture": "amd64",
        "Os": "linux",
        "Size": 231271371,
        "VirtualSize": 231271371,
        "GraphDriver": {
            "Name": "overlay2",
            "Data": {
                "LowerDir": "/var/lib/docker/overlay2/843dbc77ffc47a10df520298667faa2eab210100602c0cd7f46d9b673c99855b/diff:/var/lib/docker/overlay2/fc11cc620c56294dde9f0bfee0cfcff75230ccdb6c365ede8ee7ef59c0fa1adb/diff:/var/lib/docker/overlay2/42663774aaa795fec9cf587674ac69ec656581a0793266619e27e9c046ab7f26/diff:/var/lib/docker/overlay2/e0631b205c685cae1fb63c2846c402151ed2180e1a892b4d3e7a132b113f5a96/diff",
                "MergedDir": "/var/lib/docker/overlay2/455ee60d8346df080a5e27938f7dac2c4852c54cac1ebf67ca94de3f3a422569/merged",
                "UpperDir": "/var/lib/docker/overlay2/455ee60d8346df080a5e27938f7dac2c4852c54cac1ebf67ca94de3f3a422569/diff",
                "WorkDir": "/var/lib/docker/overlay2/455ee60d8346df080a5e27938f7dac2c4852c54cac1ebf67ca94de3f3a422569/work"
            }
        },
        "RootFS": {
            "Type": "layers",
            "Layers": [
                "sha256:74ddd0ec08fa43d09f32636ba91a0a3053b02cb4627c35051aff89f853606b59",
                "sha256:b5b47092ccb398a894e968cd669a810a5a2de62a12fb87f34432a91764729b47",
                "sha256:9c94c178db9516b69960d4d0c6fdc33a3a38c9f2652f5f9b16909944d2000d69",
                "sha256:8be7ceabf607fc7aca16766ea314167e20f8753eb2cbf959992572215b6b71e8",
                "sha256:092fc5bdc8fa52c38a1e1957a3169a2d1e8b1fe47c409d851f1eb11f762622b1"
            ]
        }
    }
]
[11-14 16:19:10 huawei root ~/dockerfile] # 


# 以这个镜像运行一个容器
[11-14 16:53:14 huawei root ~/dockerfile] # docker run --name testdockerfile_2 -it -p 8888 test:dockerfile /bin/bash
[root@53f420731914 home]# 

# 第4步，新增的挂载点

[root@53f420731914 ~]# ls -l /test_dockerfile_datavolume/
total 0
[root@53f420731914 ~]# df -Th |  grep test
/dev/vda1      ext4      40G   14G   24G  37% /test_dockerfile_datavolume

# 第5步，新增的文件，默认的工作目录是/

[root@53f420731914 ~]# ls -l /test_run_command 
-rw-r--r-- 1 root root 0 Nov 14 07:27 /test_run_command

# 第6步，进行workdir切换，登录以后默认是root用户，工作目录与workdir对应为/home
[root@53f420731914 home]# whoami 
root
[root@53f420731914 home]# pwd
/home

# 第7步，在workdir创建的文件

[root@53f420731914 home]# 
[root@53f420731914 home]# ls -l
total 0
-rw-r--r-- 1 root root 0 Nov 14 07:27 test_run_command

# 第8步，因为CMD要被覆盖，所以并没有创建文件

[root@53f420731914 ~]# ls -l /home/
total 0
-rw-r--r-- 1 root root 0 Nov 14 07:27 test_run_command

# 第9步，中将dockerfile同目录下的文件拷问到/var/log

[root@53f420731914 ~]# ls -l /var/log/test_copy.file 
-rw-r--r-- 1 root root 20 Nov 14 07:26 /var/log/test_copy.file

# 第10步，ADD可以从远端拷贝文件到镜像中

[root@53f420731914 ~]# ls -l /etc/yum.repos.d/test.repo 
-rw------- 1 root root 2495 Aug  4 07:04 /etc/yum.repos.d/test.repo
[root@53f420731914 ~]# cat /etc/yum.repos.d/test.repo  |  wc -
     56     149    2495 -

# 第11步，ARG仅对build生效，run的时候没有这个变量

[root@53f420731914 ~]# env |  grep autho

# 第12步，label的信息对镜像起作用，可以通过docker image inspect查看

[11-14 17:12:43 huawei root ~/dockerfile] # docker inspect test:dockerfile  |  grep -A 4 Labels
            "Labels": {
                "author": "huanhuan",
                "mathor": "this is a image build from centos ",
                "org.label-schema.build-date": "20210915",
                "org.label-schema.license": "GPLv2",

# 第13步，配置ENV变量

[root@53f420731914 home]# env |  grep user
testuser=test

# 第14步，查看新建的用户，因为CMD命令会被覆盖，所以14\15\16\17都会执行异常

# 对14-17进行了修改，使用RUN 替代 CMD
    14  RUN useradd $testuser
    15  USER $testuser
    16  WORKDIR /home/$testuser        # 解决问题，test没法在/home创建文件
    17  RUN touch test_file_user
    18  USER root

# 这样就会多出test用户
[root@53f420731914 home]# id test
uid=1000(test) gid=1000(test) groups=1000(test)

# 用户的切换和文件创建都可以正常下发
[root@b3bd981c2b8f test]# ls -l
total 0
-rw-r--r-- 1 test test 0 Nov 14 16:15 test_file_user
-rw-r--r-- 1 root root 0 Nov 14 16:15 test_file_user_2

# 第18步，以test:dockerfile_2这个镜像再次作为FROM创建镜像时，onbuild命令将执行

# 这个地方我反复测试了很多次，真正体会到了CMD的特点，他真的会被覆盖，哪怕是在ONBUILD后面也要被覆盖，所以后面我修改了onbuild的命令为:
ONBUILD ADD https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo ./test_onbuild_command

# 然后再次封装以后，测试就正常了。

[11-14 23:41:46 huawei root ~/dockerfile] # cat Dockerfile 
FROM test:dockerfile_2
MAINTAINER huan
ENTRYPOINT tail -F /var/log/sssss 

[11-14 23:54:37 huawei root ~/dockerfile] # docker build -t "test:onbuild" .
Sending build context to Docker daemon 6.144 kB
Step 1/3 : FROM test:dockerfile_2
# Executing 1 build trigger...
Step 1/1 : ADD https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo ./test_onbuild_command
Downloading [==================================================>] 2.495 kB/2.495 kB
 ---> 0e853ee58e88
Removing intermediate container acdb4b01ff99
Step 2/3 : MAINTAINER huan
 ---> Running in 239002c5c267
 ---> a5890608d479
Removing intermediate container 239002c5c267
Step 3/3 : ENTRYPOINT tail -F /var/log/sssss
 ---> Running in 4f8e71febf5d
 ---> d27c66d32037
Removing intermediate container 4f8e71febf5d
Successfully built d27c66d32037

[11-14 23:54:46 huawei root ~/dockerfile] # docker run -itd test:onbuild bash
92cf5fb9bf7fab200beaaf5ec7d70a54320d738c0c32a542db261dcbe9658f51
[11-14 23:54:55 huawei root ~/dockerfile] # docker exec -it 92cf5fb9bf7fab200beaaf5ec7d70a54320d738c0c32a542db261dcbe9658f51 bash
[root@92cf5fb9bf7f home]# ls
test_onbuild_command  test_run_command_2
标签：14,--,root,---,Step,test,K8S,dockerfile
From： https://www.cnblogs.com/woshinidaye123/p/16907341.html
每天一点基础K8S--dockerfile练习

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