http://vault.centos.org/7.4.1708/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found

http://vault.centos.org/7.4.1708/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
Пробуем другое зеркало.
To address this issue please refer to the below wiki article  

https://wiki.centos.org/yum-errors

If above article doesn't help to resolve this issue please use https://bugs.centos.org/.



One of the configured repositories failed (CentOS-7.4.1708 - Base),
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=C7.4.1708-base ...

    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 C7.4.1708-base
       or
           subscription-manager repos --disable=C7.4.1708-base

    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=C7.4.1708-base.skip_if_unavailable=true

failure: repodata/repomd.xml from C7.4.1708-base: [Errno 256] No more mirrors to try.
http://vault.centos.org/7.4.1708/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
Error: yum install failed

yum install yum-utils
yum-config-manager --save --setopt=C7.4.1708-base.skip_if_unavailable=true
yum-config-manager --save --setopt=C7.4.1708-updates.skip_if_unavailable=true