yum update
Loaded plugins: fastestmirror, ovl
Determining fastest mirrors
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
One of the configured repositories failed (Unknown),
and yum doesn't have enough cached data to continue. At this point the only
safe thing yum can do is fail. There are a few ways to work "fix" this:
1. Contact the upstream for the repository and get them to fix the problem.
2. Reconfigure the baseurl/etc. for the repository, to point to a working
upstream. This is most often useful if you are using a newer
distribution release than is supported by the repository (and the
packages for the previous distribution release still work).
3. Run the command with the repository temporarily disabled
yum --disablerepo=
4. Disable the repository permanently, so yum won't use it by default. Yum
will then just ignore the repository until you permanently enable it
again or use --enablerepo for temporary usage:
yum-config-manager --disable
or
subscription-manager repos --disable=
5. Configure the failing repository to be skipped, if it is unavailable.
Note that yum will try to contact the repo. when it runs most commands,
so will have to try and fail each time (and thus. yum will be be much
slower). If it is a very temporary problem though, this is often a nice
compromise:
yum-config-manager --save --setopt=
Cannot find a valid baseurl for repo: base/7/x86_64
The issue is that CentOS 7 went EOL in June 2024, but you can still access the packages in the CentOS vault for the last 7.9.2009 release for testing purposes or to create an environment to update to AlmaLinux or another newer distro.
Solution - Replace the contents of the Base Repo file "/etc/yum.repos.d/CentOS-Base.repo" as below:
[base]
name=CentOS-$releasever - Base
baseurl=http://vault.centos.org/7.9.2009/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
[updates]
name=CentOS-$releasever - Updates
baseurl=http://vault.centos.org/7.9.2009/updates/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
[extras]
name=CentOS-$releasever - Extras
baseurl=http://vault.centos.org/7.9.2009/extras/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
[centosplus]
name=CentOS-$releasever - Plus
baseurl=http://vault.centos.org/7.9.2009/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
yum install centos-release-scl
/etc/yum.repos.d/CentOS-SCLo-scl.repo
[centos-sclo-sclo]
name=CentOS-7 - SCLo sclo
baseurl=http://vault.centos.org/7.9.2009/sclo/$basearch/sclo/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
[centos-sclo-sclo-source]
name=CentOS-7 - SCLo sclo Source
baseurl=http://vault.centos.org/7.9.2009/sclo/Source/sclo/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
/etc/yum.repos.d/CentOS-SCLo-scl
[centos-sclo-rh]
name=CentOS-7 - SCLo rh
baseurl=http://vault.centos.org/7.9.2009/sclo/$basearch/rh/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
[centos-sclo-rh-source]
name=CentOS-7 - SCLo rh Source
baseurl=http://vault.centos.org/7.9.2009/sclo/Source/rh/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
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