Dockerfile（超级详细）
Dockerfile 基础知识
FROM #基础镜像，一切从这里开始构建
MAINTAINER #镜像是谁写的，姓名+邮箱
RUN #镜像构建的时候需要运行的命令
ADD #步骤，tomcat镜像，这个tomcat的压缩包！添加内容
WORKDIR #镜像的工作目录
VOLUME #挂载的目录
EXPOSE #暴露端口配置
CMD #指定这个容器启动的时候要运行的命令，只有最后一个会生效，可被替代
ENTRYPOINT #指定这个容器启动的时候要运行的命令，可以追加命令
ONBUILD #当构建一个被继承 Dockerfile 这个时候就会运行ONBUILD 的指令
COPY #类似ADD，将我们文件拷贝到镜像中
ENV #构建的时候设置环境遍量实战测试
Docker Hub 中 99% 镜像都是从这个基础镜像过来的 FROM scratch,然后配置需要的软件和配置来进行构建的
#创建一个自己的centos
#编写Dockerfile 文件
[root@root dockerfile01]# cat mydockerfile
FROM centos
MAINTAINER Hang<[email protected]>
ENV MYPATH /usr/local
WORKDIR $MYPATH
RUN yum -y install vim
RUN yum -y install net-tools
EXPOSE 80
CMD echo $MYPATH
CMD echo "----END----"
CMD /bin/bash
#通过这个文件构建镜像
#docker build -f dockerfile文件路径 -t 镜像名:[tag] .
[root@root dockerfile]# docker build -f mydockerfile -t mycentos1.0 .
Removing intermediate container 59cd03ecce3f
---> 89ba49a34e1e
Step 7/10 : EXPOSE 80
---> Running in a1efee3b0fe2
Removing intermediate container a1efee3b0fe2
---> e58f7bcccc27
Step 8/10 : CMD echo $MYPATH
---> Running in e882afef45eb
Removing intermediate container e882afef45eb
---> 906c0671d05c
Step 9/10 : CMD echo "----END----"
---> Running in f4ecc2caf6af
Removing intermediate container f4ecc2caf6af
---> 6f4bef42e0fc
Step 10/10 : CMD /bin/bash
---> Running in 44f884f709c9
Removing intermediate container 44f884f709c9
---> e6062ccf13fd
Successfully built e6062ccf13fd
Successfully tagged mycentos1.0:latest
#测试运行
[root@root dockerfile]# docker run -it mycentos1.0 /bin/bash
[root@f408b8773605 local]# pwd
/usr/local
我们可以列出本地镜像的变更历史
[root@root dockerfile]# docker history mycentos1.0
IMAGE CREATED CREATED BY SIZE COMMENT
e6062ccf13fd 6 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "/bin… 0B
6f4bef42e0fc 6 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "echo… 0B
906c0671d05c 6 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "echo… 0B
e58f7bcccc27 6 minutes ago /bin/sh -c #(nop) EXPOSE 80 0B
89ba49a34e1e 6 minutes ago /bin/sh -c yum -y install net-tools 23.4MB
2ba5aff6da20 6 minutes ago /bin/sh -c yum -y install vim 58.1MB
e34dc5e2146b 7 minutes ago /bin/sh -c #(nop) WORKDIR /usr/local 0B
bd4017671eca 7 minutes ago /bin/sh -c #(nop) ENV MYPATH=/usr/local 0B
f23b466173fb 7 minutes ago /bin/sh -c #(nop) MAINTAINER root<175480… 0B
300e315adb2f 6 weeks ago /bin/sh -c #(nop) CMD ["/bin/bash"] 0B
6 weeks ago /bin/sh -c #(nop) LABEL org.label-schema.sc… 0B
6 weeks ago /bin/sh -c #(nop) ADD file:bd7a2aed6ede423b7… 209MB CMD 和 ENTRYPOINT 区别
CMD #指定这个容器启动的时候要运行的命令，只有最后一个会生效，可被替代
ENTRYPOINT #指定这个容器启动的时候要运行的命令，可以追加命令
测试cmd
# 编写dockerfile文件
[root@root dockerfile]# vi dockerfile-cmd
FROM centos
CMD ["ls","-a"]
# 构建镜像
[root@root dockerfile]# docker build -f dockerfile-cmd -t cmd .
Sending build context to Docker daemon 3.072kB
Step 1/2 : FROM centos
---> 300e315adb2f
Step 2/2 : CMD ["ls","-a"]
---> Running in 711a369ca8ce
Removing intermediate container 711a369ca8ce
---> 96c1a6a5a855
Successfully built 96c1a6a5a855
Successfully tagged cmd:latest
# run 运行 发现我们的 ls -a 命令生效
[root@root dockerfile]# docker run 96c1a6a5a855
.
..
.dockerenv
bin
dev
etc
home
lib
lib64
lost+found
media
mnt
opt
proc
root
run
sbin
srv
sys
tmp
usr
var
# 想追加一个命令 -l ls -al
[root@root dockerfile]# docker run 96c1a6a5a855 -l
docker: Error response from daemon: OCI runtime create failed: container_linux.go:370: starting container process caused: exec: "-l": executable file not found in $PATH: unknown.
# cmd 的情况下 -l 替换了 CMD ["ls","-a"] 命令 -l 不是命令 所以报错
测试ENTRYPOINT
# 编写dockerfile文件
[root@root dockerfile]# vi dockerfile-entrypoint
# 构建镜像
[root@root dockerfile]# docker build -f dockerfile-entrypoint -t entrypoint .
Sending build context to Docker daemon 4.096kB
Step 1/2 : FROM centos
---> 300e315adb2f
Step 2/2 : ENTRYPOINT ["ls","-a"]
---> Running in 198ab82ed16c
Removing intermediate container 198ab82ed16c
---> 951f0c5be0f2
Successfully built 951f0c5be0f2
Successfully tagged entrypoint:latest
# run 运行 发现我们的 ls -a 命令生效
[root@root dockerfile]# docker run 951f0c5be0f2
.
..
.dockerenv
bin
dev
etc
home
lib
lib64
lost+found
media
mnt
opt
proc
root
run
sbin
srv
sys
tmp
usr
var
# 想追加一个命令 -l ls -al 发现生效
[root@root dockerfile]# docker run 951f0c5be0f2 -l
total 0
drwxr-xr-x. 1 root root 6 Jan 22 16:08 .
drwxr-xr-x. 1 root root 6 Jan 22 16:08 ..
-rwxr-xr-x. 1 root root 0 Jan 22 16:08 .dockerenv
lrwxrwxrwx. 1 root root 7 Nov 3 15:22 bin -> usr/bin
drwxr-xr-x. 5 root root 340 Jan 22 16:08 dev
drwxr-xr-x. 1 root root 66 Jan 22 16:08 etc
drwxr-xr-x. 2 root root 6 Nov 3 15:22 home
lrwxrwxrwx. 1 root root 7 Nov 3 15:22 lib -> usr/lib
lrwxrwxrwx. 1 root root 9 Nov 3 15:22 lib64 -> usr/lib64
drwx------. 2 root root 6 Dec 4 17:37 lost+found
drwxr-xr-x. 2 root root 6 Nov 3 15:22 media
drwxr-xr-x. 2 root root 6 Nov 3 15:22 mnt
drwxr-xr-x. 2 root root 6 Nov 3 15:22 opt
dr-xr-xr-x. 240 root root 0 Jan 22 16:08 proc
dr-xr-x---. 2 root root 162 Dec 4 17:37 root
drwxr-xr-x. 11 root root 163 Dec 4 17:37 run
lrwxrwxrwx. 1 root root 8 Nov 3 15:22 sbin -> usr/sbin
drwxr-xr-x. 2 root root 6 Nov 3 15:22 srv
dr-xr-xr-x. 13 root root 0 Jan 22 13:11 sys
drwxrwxrwt. 7 root root 145 Dec 4 17:37 tmp
drwxr-xr-x. 12 root root 144 Dec 4 17:37 usr
drwxr-xr-x. 20 root root 262 Dec 4 17:37 var
实战：tomcat镜像
1、准备镜像文件 tomcat压缩包 、jdk压缩包
apache-tomcat-9.0.22.tar.gz
jdk-8u11-linux-x64.tar.gz
2、编写dockerfile文件 官方命名 Dockerfile ，build会自动寻找这个文件 就不需要 -f 指定了
[root@root tomcat]# cat Dockerfile
FROM centos
MAINTAINER Hang<[email protected]>
COPY readme.txt /usr/local/readme.txt
ADD jdk-8u11-linux-x64.tar.gz /usr/local/
ADD apache-tomcat-9.0.22.tar.gz /usr/local/
RUN yum -y install vim
ENV MYPATH /usr/local
WORKDIR $MYPATH
ENV JAVA_HOME /usr/local/jdk1.8.0_11
ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
ENV CATALINA_HOME /usr/local/apache-tomcat-9.0.22
ENV CATALINA_BASH /usr/local/apache-tomcat-9.0.22
ENV PATH $PATH:$JAVA_HOME/bin:$CATALINA_HOME/lib:$CATALINA_HOME/bin
EXPOSE 8080
CMD /usr/local/apache-tomcat-9.0.22/startup.sh && tail -F /usr/local/apache-tomcat-9.0.22/bin/logs/catalina.out3、构建镜像
# docker build -t diytomcat .
Removing intermediate container 8ae0bf3da639
---> 731ad02de5b7
Step 7/15 : ENV MYPATH /usr/local
---> Running in 096e09b9bc21
Removing intermediate container 096e09b9bc21
---> 4af21aee2224
Step 8/15 : WORKDIR $MYPATH
---> Running in 754abbc7213e
Removing intermediate container 754abbc7213e
---> b90b463448c6
Step 9/15 : ENV JAVA_HOME /usr/local/jdk1.8.0_11
---> Running in 8d88b767e5ba
Removing intermediate container 8d88b767e5ba
---> 8be538aa441f
Step 10/15 : ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
---> Running in 2d474aacec81
Removing intermediate container 2d474aacec81
---> d2a196f068ee
Step 11/15 : ENV CATALINA_HOME /usr/local/apache-tomcat-9.0.22
---> Running in 57b51e71729c
Removing intermediate container 57b51e71729c
---> 82bc59fffad0
Step 12/15 : ENV CATALINA_BASH /usr/local/apache-tomcat-9.0.22
---> Running in 132900cd06c0
Removing intermediate container 132900cd06c0
---> 26764aa6f6e6
Step 13/15 : ENV PATH $PATH:$JAVA_HOME/bin:$CATALINA_HOME/lib:$CATALINA_HOME/bin
---> Running in dd532def866f
Removing intermediate container dd532def866f
---> 20a93b435b70
Step 14/15 : EXPOSE 8080
---> Running in 791216126e87
Removing intermediate container 791216126e87
---> 6187b918f77d
Step 15/15 : CMD /usr/local/apache-tomcat-9.0.22/bin/startup.sh && tail -F /url/local/apache-tomcat-9.0.22/bin/logs/catalina.out
---> Running in 1aee1676f7d3
Removing intermediate container 1aee1676f7d3
---> 0c58fc779b7a
Successfully built 0c58fc779b7a
Successfully tagged dirtomcat:latest启动容器，出现错误
启动镜像，ID出来，可是docker ps 发现没有运行
使用docker logs 容器ID 查看报错内容
出现 /bin/startup.sh:Pemission denied
解决方法
进入容器
#启动容器
[root@root tomcat]# docker run -it -d dirtomcat /bin/bash
f6dfac5e79aedf94afb79c9797aebb3f198a0b17a297b94ba72e5a686d7a0741
#查看正在运行的容器
[root@root tomcat]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f6dfac5e79ae dirtomcat "/bin/bash" 2 seconds ago Up 1 second 8080/tcp strange_keller
#进入容器
[root@root tomcat]# docker exec -it f6dfac5e79ae /bin/bash
[root@f6dfac5e79ae local]# ls
apache-tomcat-9.0.22 bin etc games include jdk1.8.0_11 lib lib64 libexec readme.txt sbin share src
#使用 startup.sh 命令 发现报错 原因是权限不够
[root@f6dfac5e79ae local]# startup.sh
bash: /usr/local/apache-tomcat-9.0.22/bin/startup.sh: Permission denied
#赋权 再启动 发现 catalina.sh 权限不够
[root@f6dfac5e79ae local]# chmod 777 /usr/local/apache-tomcat-9.0.22/bin/startup.sh
[root@f6dfac5e79ae local]# startup.sh
Cannot find /usr/local/apache-tomcat-9.0.22/bin/catalina.sh
The file is absent or does not have execute permission
This file is needed to run this program
#继续给 catalina.sh 赋权
[root@f6dfac5e79ae /]# chmod 777 /usr/local/apache-tomcat-9.0.22/bin/catalina.sh
#再次启动 tomcat 启动成功
[root@f6dfac5e79ae /]# startup.sh
Using CATALINA_BASE: /usr/local/apache-tomcat-9.0.22
Using CATALINA_HOME: /usr/local/apache-tomcat-9.0.22
Using CATALINA_TMPDIR: /usr/local/apache-tomcat-9.0.22/temp
Using JRE_HOME: /usr/local/jdk1.8.0_11
Using CLASSPATH: /usr/local/apache-tomcat-9.0.22/bin/bootstrap.jar:/usr/local/apache-tomcat-9.0.22/bin/tomcat-juli.jar
那么我们修改一下dockerfile文件内容
[root@root tomcat]# cat Dockerfile
FROM centos
MAINTAINER root<[email protected]>
COPY readme.txt /usr/local/readme.txt
ADD jdk-8u11-linux-x64.tar.gz /usr/local/
ADD apache-tomcat-9.0.22.tar.gz /usr/local/
RUN yum -y install vim
RUN chmod 777 /usr/local/apache-tomcat-9.0.22/bin/startup.sh
RUN chmod 777 /usr/local/apache-tomcat-9.0.22/bin/catalina.sh
ENV MYPATH /usr/local
WORKDIR $MYPATH
ENV JAVA_HOME /usr/local/jdk1.8.0_11
ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
ENV CATALINA_HOME /usr/local/apache-tomcat-9.0.22
ENV CATALINA_BASH /usr/local/apache-tomcat-9.0.22
ENV PATH $PATH:$JAVA_HOME/bin:$CATALINA_HOME/lib:$CATALINA_HOME/bin
EXPOSE 8080
CMD /usr/local/apache-tomcat-9.0.22/bin/startup.sh && tail -F /usr/local/apache-tomcat-9.0.22/bin/logs/catalina.out构建镜像
[root@root tomcat]# docker build -t lh_tomcat .
Sending build context to Docker daemon 169.9MB
Step 1/17 : FROM centos
---> 300e315adb2f
Step 2/17 : MAINTAINER root<[email protected]>
---> Using cache
---> f23b466173fb
Step 3/17 : COPY readme.txt /usr/local/readme.txt
---> Using cache
---> 5dfad04cae31
Step 4/17 : ADD jdk-8u11-linux-x64.tar.gz /usr/local/
---> Using cache
---> e15afd0717d9
Step 5/17 : ADD apache-tomcat-9.0.22.tar.gz /usr/local/
---> Using cache
---> 8b3b0b260f0c
Step 6/17 : RUN yum -y install vim
---> Using cache
---> 731ad02de5b7
Step 7/17 : RUN chmod 777 /usr/local/apache-tomcat-9.0.22/bin/startup.sh
---> Using cache
---> e60e5bb8d68d
Step 8/17 : RUN chmod 777 /usr/local/apache-tomcat-9.0.22/bin/catalina.sh
---> Using cache
---> 1bdadcf5f05c
Step 9/17 : ENV MYPATH /usr/local
---> Running in dc5f851a95aa
Removing intermediate container dc5f851a95aa
---> 567826b1db9b
Step 10/17 : WORKDIR $MYPATH
---> Running in a1b9fa1f25c8
Removing intermediate container a1b9fa1f25c8
---> f2da44f2566d
Step 11/17 : ENV JAVA_HOME /usr/local/jdk1.8.0_11
---> Running in 1525576adae9
Removing intermediate container 1525576adae9
---> 422a260a9854
Step 12/17 : ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
---> Running in ff3679d3d0d7
Removing intermediate container ff3679d3d0d7
---> 1f2fb5b405ce
Step 13/17 : ENV CATALINA_HOME /usr/local/apache-tomcat-9.0.22
---> Running in c627139c2a0e
Removing intermediate container c627139c2a0e
---> 941804071257
Step 14/17 : ENV CATALINA_BASH /usr/local/apache-tomcat-9.0.22
---> Running in 201a8d7d454b
Removing intermediate container 201a8d7d454b
---> 6a3edac3ea02
Step 15/17 : ENV PATH $PATH:$JAVA_HOME/bin:$CATALINA_HOME/lib:$CATALINA_HOME/bin
---> Running in 5403ebe0c029
Removing intermediate container 5403ebe0c029
---> 3de5361ec881
Step 16/17 : EXPOSE 8080
---> Running in a1e4f56c1cb5
Removing intermediate container a1e4f56c1cb5
---> 98fd728337df
Step 17/17 : CMD /usr/local/apache-tomcat-9.0.22/bin/startup.sh && tail -F /usr/local/apache-tomcat-9.0.22/bin/logs/catalina.out
---> Running in 3b183e06aecd
Removing intermediate container 3b183e06aecd
---> 9fcc0d5c6a4e
Successfully built 9fcc0d5c6a4e
Successfully tagged lh_tomcat:latest重新启动容器
#启动
[root@root tomcat]# docker run -d -p 9100:8080 --name lh_tomcat -v /home/tomcat/test:/usr/local/apache-tomcat-9.0.22/webapps/test -v /home/tomcat/tomcatlogs/:/usr/local/apache-tomcat-9.0.22/logs lh_tomcat
57f64d17045fe343a60cbbec368cac9b0a201a181253903828bb8cbb2a73e51d
#查看正在运行的容器，发现正在运行
[root@root tomcat]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
57f64d17045f lh_tomcat "/bin/sh -c '/usr/lo…" 2 seconds ago Up 2 seconds 0.0.0.0:9100->8080/tcp lh_tomcat#### 访问测试
##### 访问 本机ip:9100
在/home/tomcat/test 下构建两个文件
web.xml
index.html
哥的页面
哥牛逼！
成功!!