构建docker基本镜像

1.准备：

创建一个目录oldboy-hello

2.编写Dockerfile

内容如下，只有三行

FROM scratch

ADD hello /

CMD ["/hello"]

当前目录下的文件

[root@linux-node1 oldboy-hello]# ls

Dockerfile hello

 

3.构建docker镜像

[root@linux-node1 oldboy-hello]# docker build -t oldboyedu/hello .

Sending build context to Docker daemon 4.608kB

Step 1/3 : FROM scratch

--->

Step 2/3 : ADD hello /

---> 0018e580ccaf

Removing intermediate container 64b74f2071e1

Step 3/3 : CMD /hello

---> Running in 6438314dc49d

---> 4a047322f97d

Removing intermediate container 6438314dc49d

Successfully built 4a047322f97d

Successfully tagged oldboyedu/hello:latest

 

4.启动容器

[root@linux-node1 oldboy-hello]# docker run --rm -it oldboyedu/hello

Welcome oldboy education!

 

5.补充

hello的是使用C语言编译之后的二进制程序

[root@linux-node1 opt]# cat hello.c

//#include <unistd.h>

#include <sys/syscall.h>

#ifndef DOCKER_IMAGE

#define DOCKER_IMAGE "hello-world"

#endif

#ifndef DOCKER_GREETING

#define DOCKER_GREETING "Welcome oldboy education!"

#endif

const char message[] =

DOCKER_GREETING "\n";

void _start() {

//write(1, message, sizeof(message) - 1);

syscall(SYS_write, 1, message, sizeof(message) - 1);

//_exit(0);

syscall(SYS_exit, 0);

}

编译命令gcc -o hello -static -nostartfiles hello.c

测试执行

[root@linux-node1 oldboy-hello]# ./hello

Welcome oldboy education!

如果编译出错

[root@linux-node1 ~]# gcc -o hello -static -nostartfiles hello.c

/usr/bin/ld: cannot find -lc

collect2: error: ld returned 1 exit status

安装glibc-static

yum install glibc-static gcc -y