編寫Dockerfile檔案

vim mydockerfile-centos

FROM centos

MAINTAINER zhaowx<549334961@qq.com>

ENV MYPATH /usr/local
WORKDIR $MYPATH

RUN yum install -y vim net-tools tcpdump

EXPOSE 80

CMD echo $MYPATH
CMD echo "---------end---------"
CMD /bin/bash

通過剛剛編寫的Dockerfile，構建映象

docker build -f mydockerfile-centos -t mycentos:0.2
 
 .

解決思路

由於centos8的官方映象已經停止維護，而docker pull預設是last版本，也就是centos8，所以有了以下兩種解決辦法

1.刪除最新映象，拉取7版本的映象

FROM centos:7.9.2009

MAINTAINER zhaowx<549334961@qq.com>

ENV MYPATH /usr/local
WORKDIR $MYPATH

RUN yum install -y vim net-tools tcpdump

EXPOSE 80

CMD echo $MYPATH
CMD echo "---------end---------"
CMD 
 
/bin/bash

2.在Dockerfile中安裝命令之前，執行修改配置，將映象改為【https://vault.centos.org】

FROM centos

MAINTAINER zhaowx<549334961@qq.com>

ENV MYPATH /usr/local
WORKDIR $MYPATH

RUN sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-*
RUN sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum
 
.repos.d/CentOS-*
RUN sed -i 's|gpgcheck=1|gpgcheck=0|g' /etc/yum.repos.d/CentOS-*

RUN yum clean all ; yum makecache
RUN yum install -y vim net-tools tcpdump

EXPOSE 80

CMD echo $MYPATH
CMD echo "---------end---------"
CMD /bin/bash