Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=stock32 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

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

    distribution release than is supported by the repository (and the

    packages for the previous distribution release still work).

 3. Disable the repository, so yum won't use it by default. Yum will

    just ignore the repository until you permanently enable it again or use

    --enablerepo for temporary usage:

        yum-config-manager --disable <repoid>

 4. 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=<repoid>.skip_if_unavailable=true

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