centos7のdocker imageを使用して環境構築時に、yumコマンド実行で突如以下のようなエラーが発生するようになった(20240701~)
0.532 Loaded plugins: fastestmirror, ovl
0.710 Determining fastest mirrors
6.226 Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was
6.226 14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
6.230
6.230
6.230 One of the configured repositories failed (Unknown),
6.230 and yum doesn't have enough cached data to continue. At this point the only
6.230 safe thing yum can do is fail. There are a few ways to work "fix" this:
6.230
6.230 1. Contact the upstream for the repository and get them to fix the problem.
6.230
6.230 2. Reconfigure the baseurl/etc. for the repository, to point to a working
6.230 upstream. This is most often useful if you are using a newer
6.230 distribution release than is supported by the repository (and the
6.230 packages for the previous distribution release still work).
6.230
6.230 3. Run the command with the repository temporarily disabled
6.230 yum --disablerepo=<repoid> ...
6.230
6.230 4. Disable the repository permanently, so yum won't use it by default. Yum
6.230 will then just ignore the repository until you permanently enable it
6.230 again or use --enablerepo for temporary usage:
6.230
6.230 yum-config-manager --disable <repoid>
6.230 or
6.230 subscription-manager repos --disable=<repoid>
6.230
6.230 5. Configure the failing repository to be skipped, if it is unavailable.
6.230 Note that yum will try to contact the repo. when it runs most commands,
6.230 so will have to try and fail each time (and thus. yum will be be much
6.230 slower). If it is a very temporary problem though, this is often a nice
6.230 compromise:
6.230
6.230 yum-config-manager --save --setopt=<repoid>.skip_if_unavailable=true
6.230
6.230 Cannot find a valid baseurl for repo: base/7/x86_64
Dockerfile
FROM centos:7
RUN yum -y update && yum clean all && \
yum -y install ...
原因
centos7のサポート終了により、mirrorlist.centos.orgが存在しなくなった様子
CentOS Linux 7 は、2024 年 6 月 30 日にサポート終了 (EOL) となります
解決策
/etc/yum.repos.d/CentOS-*.repoからmirrorlistのコメントアウトとbaseurlの書き換えを行い、サポート終了後のリポジトリを参照するように
e.g. /etc/yum.repos.d/CentOS-Base.repo
- before
[base]
name=CentOS-$releasever - Base
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra
#baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
...
- after
[base]
name=CentOS-$releasever - Base
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra
baseurl=http://vault.centos.org/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
...
dockerfileでこの書き換えをyum実行前に指定する
FROM centos:7
RUN sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-* && \
sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-* && \
yum -y update && yum clean all && \
yum -y install ...