场景

使用自定义Dockerfile构建Redis镜像时，出现了异常
Dockerfile文件内容如下：

FROM centos
RUN ["yum","install","-y","gcc","gcc-c++","net-tools","make"]
WORKDIR /docker/docker-redis
ADD redis-4.0.14.tar.gz .
WORKDIR /docker/docker-redis/redis-4.0.14/src
RUN make && make install
WORKDIR /docker/docker-redis/redis-4.0.14
ADD redis-7000.conf .
EXPOSE 7000
CMD ["redis-server","redis-7000.conf"]

遇到的问题

[root@localhost docker-redis]# docker build -t forlan.com/docker-redis .
[+] Building 2.2s (6/12)                                                                                                                                             docker:default=> [internal] load build definition from Dockerfile                                                                                                                           0.0s=> => transferring dockerfile: 416B                                                                                                                                           0.0s=> [internal] load .dockerignore                                                                                                                                              0.1s=> => transferring context: 2B                                                                                                                                                0.0s=> [internal] load metadata for docker.io/library/centos:latest                                                                                                               0.3s=> CACHED [1/8] FROM docker.io/library/centos@sha256:a27fd8080b517143cbbbab9dfb7c8571c40d67d534bbdee55bd6c473f432b177                                                         0.0s=> [internal] load build context                                                                                                                                              0.0s=> => transferring context: 190B                                                                                                                                              0.0s=> ERROR [2/8] RUN ["yum" , "install" , "-y" ,"gcc","gcc-c++","net-tools","make"]                                                                                             1.7s
------> [2/8] RUN ["yum" , "install" , "-y" ,"gcc","gcc-c++","net-tools","make"]:
1.603 Error: Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist
1.603 CentOS Linux 8 - AppStream                       57  B/s |  38  B     00:00    
------
Dockerfile:2
--------------------1 |     FROM centos2 | >>> RUN ["yum" , "install" , "-y" ,"gcc","gcc-c++","net-tools","make"]3 |     WORKDIR /docker/docker-redis4 |     ADD redis-4.0.14.tar.gz .
--------------------
ERROR: failed to solve: process "yum install -y gcc gcc-c++ net-tools make" did not complete successfully: exit code: 1

解决

在2020 年 12 月 8 号，CentOS 官方宣布了停止维护 CentOS Linux 的计划，并推出了 CentOS Stream 项目，CentOS Linux 8 作为 RHEL 8 的复刻版本，生命周期缩短，于 2021 年 12 月 31 日停止更新并停止维护（EOL）

1、增加内容

主要增加以下内容，修改yum包管理器的源配置

RUN cd /etc/yum.repos.d/
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 yum update -y

完整内容如下：

FROM centos
RUN cd /etc/yum.repos.d/
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 yum update -y
RUN ["yum" , "install" , "-y" ,"gcc","gcc-c++","net-tools","make"]
WORKDIR /docker/docker-redis
ADD redis-4.0.14.tar.gz .
WORKDIR /docker/docker-redis/redis-4.0.14/src
RUN make && make install
WORKDIR /docker/docker-redis/redis-4.0.14
ADD redis-7000.conf .
EXPOSE 7000
CMD ["redis-server","redis-7000.conf"]

2、调整内容

FROM centos-》FROM centos:centos7